diff --git a/npm-shrinkwrap.json b/npm-shrinkwrap.json
index d46d28eb88..d6b8e8ef46 100644
--- a/npm-shrinkwrap.json
+++ b/npm-shrinkwrap.json
@@ -36,7 +36,7 @@
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-          "resolved": "http://registry.npmjs.org/acorn/-/acorn-3.3.0.tgz",
+          "resolved": "https://registry.npmjs.org/acorn/-/acorn-3.3.0.tgz",
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-      "resolved": "https://registry.npmjs.org/async/-/async-1.5.2.tgz",
-      "integrity": "sha1-7GphrlZIDAw8skHJVhjiCJL5Zyo=",
-      "dev": true
+      "version": "2.6.4",
+      "resolved": "https://registry.npmjs.org/async/-/async-2.6.4.tgz",
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+      "dev": true,
+      "requires": {
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+      "dependencies": {
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+          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.21.tgz",
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+        }
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-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
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@@ -654,7 +665,7 @@
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-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
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@@ -688,7 +699,7 @@
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-          "resolved": "http://registry.npmjs.org/yargs/-/yargs-1.3.3.tgz",
+          "resolved": "https://registry.npmjs.org/yargs/-/yargs-1.3.3.tgz",
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-          "resolved": "http://registry.npmjs.org/rimraf/-/rimraf-2.0.3.tgz",
+          "resolved": "https://registry.npmjs.org/rimraf/-/rimraf-2.0.3.tgz",
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@@ -1139,7 +1150,7 @@
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-          "resolved": "http://registry.npmjs.org/onetime/-/onetime-1.1.0.tgz",
+          "resolved": "https://registry.npmjs.org/onetime/-/onetime-1.1.0.tgz",
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@@ -1603,7 +1614,7 @@
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-          "resolved": "http://registry.npmjs.org/combined-stream/-/combined-stream-1.0.6.tgz",
+          "resolved": "https://registry.npmjs.org/combined-stream/-/combined-stream-1.0.6.tgz",
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@@ -1891,7 +1902,7 @@
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-          "resolved": "http://registry.npmjs.org/lodash/-/lodash-4.13.1.tgz",
+          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.13.1.tgz",
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@@ -2047,7 +2058,7 @@
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-          "resolved": "http://registry.npmjs.org/rimraf/-/rimraf-2.2.8.tgz",
+          "resolved": "https://registry.npmjs.org/rimraf/-/rimraf-2.2.8.tgz",
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@@ -2065,9 +2076,15 @@
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+          "resolved": "https://registry.npmjs.org/async/-/async-1.5.2.tgz",
+          "integrity": "sha1-7GphrlZIDAw8skHJVhjiCJL5Zyo=",
+          "dev": true
+        },
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-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
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@@ -2104,7 +2121,7 @@
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-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
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@@ -2138,9 +2155,15 @@
         "tiny-lr": "^0.2.1"
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+          "resolved": "https://registry.npmjs.org/async/-/async-1.5.2.tgz",
+          "integrity": "sha1-7GphrlZIDAw8skHJVhjiCJL5Zyo=",
+          "dev": true
+        },
         "lodash": {
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-          "resolved": "http://registry.npmjs.org/lodash/-/lodash-3.10.1.tgz",
+          "resolved": "https://registry.npmjs.org/lodash/-/lodash-3.10.1.tgz",
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@@ -2186,7 +2209,7 @@
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-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
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@@ -2199,7 +2222,7 @@
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-          "resolved": "http://registry.npmjs.org/lodash/-/lodash-4.3.0.tgz",
+          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.3.0.tgz",
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           "dev": true
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@@ -2229,9 +2252,15 @@
         "which": "~1.2.1"
       },
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+        "async": {
+          "version": "1.5.2",
+          "resolved": "https://registry.npmjs.org/async/-/async-1.5.2.tgz",
+          "integrity": "sha1-7GphrlZIDAw8skHJVhjiCJL5Zyo=",
+          "dev": true
+        },
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-          "resolved": "http://registry.npmjs.org/lodash/-/lodash-4.3.0.tgz",
+          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.3.0.tgz",
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@@ -3120,7 +3149,7 @@
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-          "resolved": "http://registry.npmjs.org/debug/-/debug-0.7.4.tgz",
+          "resolved": "https://registry.npmjs.org/debug/-/debug-0.7.4.tgz",
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@@ -3231,7 +3260,7 @@
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-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
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@@ -3311,7 +3340,7 @@
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-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
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@@ -3532,7 +3561,7 @@
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-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
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@@ -3943,7 +3972,7 @@
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-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
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-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
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@@ -4845,7 +4874,7 @@
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-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
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@@ -4931,7 +4960,7 @@
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-          "resolved": "http://registry.npmjs.org/autoprefixer/-/autoprefixer-7.2.6.tgz",
+          "resolved": "https://registry.npmjs.org/autoprefixer/-/autoprefixer-7.2.6.tgz",
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@@ -5008,7 +5037,7 @@
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-              "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+              "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
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@@ -5075,7 +5104,7 @@
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-              "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+              "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
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@@ -5155,7 +5184,7 @@
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-          "resolved": "http://registry.npmjs.org/lodash/-/lodash-3.10.1.tgz",
+          "resolved": "https://registry.npmjs.org/lodash/-/lodash-3.10.1.tgz",
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@@ -5402,7 +5431,7 @@
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-          "resolved": "http://registry.npmjs.org/debug/-/debug-2.2.0.tgz",
+          "resolved": "https://registry.npmjs.org/debug/-/debug-2.2.0.tgz",
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@@ -5771,7 +5800,7 @@
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-      "resolved": "http://registry.npmjs.org/yargs/-/yargs-3.10.0.tgz",
+      "resolved": "https://registry.npmjs.org/yargs/-/yargs-3.10.0.tgz",
       "integrity": "sha1-9+572FfdfB0tOMDnTvvWgdFDH9E=",
       "dev": true,
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diff --git a/package.json b/package.json
index 6e20b6c954..137a7a121f 100644
--- a/package.json
+++ b/package.json
@@ -3,7 +3,7 @@
   "private": true,
   "description": "Moodle",
   "devDependencies": {
-    "async": "1.5.2",
+    "async": "2.6.4",
     "eslint": "4.6.1",
     "eslint-plugin-promise": "3.5.0",
     "gherkin-lint": "1.1.3",