Sync metadata

exercises/practice/binary-search-tree/.meta/config.json

@@ -34,6 +34,5 @@
     ]
   },
   "blurb": "Insert and search for numbers in a binary tree.",
-  "source": "Josh Cheek",
-  "source_url": "https://twitter.com/josh_cheek"
+  "source": "Josh Cheek"
 }

exercises/practice/clock/.meta/config.json

@@ -40,6 +40,5 @@
     ]
   },
   "blurb": "Implement a clock that handles times without dates.",
-  "source": "Pairing session with Erin Drummond",
-  "source_url": "https://twitter.com/ebdrummond"
+  "source": "Pairing session with Erin Drummond"
 }

exercises/practice/meetup/.meta/config.json

@@ -35,5 +35,5 @@
   },
   "blurb": "Calculate the date of meetups.",
   "source": "Jeremy Hinegardner mentioned a Boulder meetup that happens on the Wednesteenth of every month",
-  "source_url": "https://twitter.com/copiousfreetime"
+  "source_url": "http://www.copiousfreetime.org/"
 }

exercises/practice/strain/.meta/config.json

@@ -31,5 +31,5 @@
   },
   "blurb": "Implement the `keep` and `discard` operation on collections. Given a collection and a predicate on the collection's elements, `keep` returns a new collection containing those elements where the predicate is true, while `discard` returns a new collection containing those elements where the predicate is false.",
   "source": "Conversation with James Edward Gray II",
-  "source_url": "https://twitter.com/jeg2"
+  "source_url": "http://graysoftinc.com/"
 }