Sending messages
Merge branch 'sandbox'

Conflicts:
	helpers/request_helpers.js
	server.js
Updated retrieveConversations method to return data in the correct format
Updated retrieveSingleConversation method so that the format of the object returned matches that of the retrieveConversations method
Conversations are now returned from the database in order, starting with the conversation that has the most recent activity
Cleaned up code
Started implementing match filters
findMatches now effectively filters by latest activity and converts the latest activity of matches into a user-friendly format before returning it to the client
findMatches is now capable of filtering matches by geo location
added commonFriendsArray helper method
fixed merge conflict
Fixed minor bugs
findMatches function now returns a list of common friends. findMatches results reformatted for the client.  Code cleaned up.
Updated retrieveConversations function to return a single object.  Still need to update retrieveSingleConversation
Updated retrieveSingleConversation method to return an object with the match name as the key and the messages array as the value.
Updated addFollowingRelationship to use MERGE instead of MATCH
Deleted db_helpers file
Fixed function names in request_helpers
Updated request helpers
Updated findMatches to accept a callback which returns matches to the client