Update xkcdViewer provider to use HTTPS URLs

xkcd.com changed to using HTTPS some time ago; the change causes
XkcdViewer to fail with "Data returned from website didn't match
expected format" as the 301 redirect is attempted to be parsed as JSON,
which obviously fails.

While this isn't a complete fix, it should hopefully fix the app enough
for it to work again.

Fixes tcoxon#70.

xkcdViewer/src/main/java/net/bytten/xkcdviewer/XkcdComicDefinition.java

@@ -25,7 +25,7 @@ public XkcdComicDefinition() {
 
     @Override
     public Uri getArchiveUrl() {
-        return Uri.parse("http://xkcd.com/archive/");
+        return Uri.parse("https://xkcd.com/archive/");
     }
 
     @Override
@@ -35,7 +35,7 @@ public String getAuthorLinkText() {
 
     @Override
     public Uri getAuthorLinkUrl() {
-        return Uri.parse("http://store.xkcd.com/");
+        return Uri.parse("https://store.xkcd.com/");
     }
 
     @Override

xkcdViewer/src/main/java/net/bytten/xkcdviewer/XkcdComicInfo.java

@@ -48,7 +48,7 @@ public String getTitle() {
 
     @Override
     public String getUrl() {
-        return "http://xkcd.com/"+getId()+"/";
+        return "https://xkcd.com/"+getId()+"/";
     }
 
     @Override

xkcdViewer/src/main/java/net/bytten/xkcdviewer/XkcdComicProvider.java

@@ -24,7 +24,7 @@ public class XkcdComicProvider implements IComicProvider {
     private static final Pattern archiveItemPattern = Pattern.compile(
             // group(1): comic number;   group(2): date;   group(3): title
             "\\s*<a href=\"/(\\d+)/\" title=\"(\\d+-\\d+-\\d+)\">([^<]+)</a><br/>\\s*");
-    private static final String ARCHIVE_URL = "http://www.xkcd.com/archive/";
+    private static final String ARCHIVE_URL = "https://www.xkcd.com/archive/";
 
     private XkcdComicDefinition def;
 
@@ -43,13 +43,13 @@ public Uri comicDataUrlForUrl(Uri url) {
 
     @Override
     public Uri createComicUrl(String comicId) {
-        return Uri.parse("http://xkcd.com/"+comicId+"/info.0.json");
+        return Uri.parse("https://xkcd.com/"+comicId+"/info.0.json");
     }
 
     @Override
     public IComicInfo fetchComicInfo(Uri url) throws Exception {
         // Uses xkcd's JSON interface
-        //      (http://xkcd.com/json.html) 
+        //      (https://xkcd.com/json.html) 
         String text = Utility.blockingReadUri(url);
         JSONObject obj = (JSONObject)new JSONTokener(text).nextValue();
         Log.d("json", obj.names().toString());
@@ -91,7 +91,7 @@ public Uri fetchRandomComicUrl() throws Exception {
 
     @Override
     public Uri getFinalComicUrl() {
-        return Uri.parse("http://xkcd.com/info.0.json");
+        return Uri.parse("https://xkcd.com/info.0.json");
     }
 
     @Override

xkcdViewer/src/main/res/values/strings.xml

@@ -9,7 +9,7 @@
     xkcdViewer v%s. Application for viewing xkcd comics with hover text.\n\n
     xkcdViewer Copyright (C) 2009-2017, Tom Coxon, Tyler Breisacher, David
     McCullough, Kristian Lundkvist.\n\n
-    xkcd is Copyright (C) 2006 - 2017, Randall Munroe (http://xkcd.com)\n\n
+    xkcd is Copyright (C) 2006 - 2017, Randall Munroe (https://xkcd.com)\n\n
     Contains some menu icons from www.androidicons.com, licensed under a
     Creative Commons Attribution - Share Alike license.\n\n
     Application icon kindly donated by Johan Larsson.\n\n