Revert "reverting groups.js to 4701eb1cee1a35b7f059f4362773bd9d67b7370c"

This reverts commit d8df9ab3edeb8f858fb89cd935070e5db4a49e62.
removing use of slugs in groups... pending having more time
removed socket emits for post errors
removed reply from not logged in error message
closes #1366
dont add dupes to widgetLocations

this prevents widgets from being executed multiple times
update to use error messages
latest translations
favourite changes

favourites.js no longer makes socket calls, moved that code into
socket.io/posts.js. it also makes a single socket call when you downvote
a post that you previously upvoted.
added error key
admin js language keys
meta.js error language keys
modules.js error keys
posts.js error keys
user.js error keys
more error strings
added lots of error keys
fixed topic test
really fixed test
LevelDB init