better file upload dialog
more vertical space in the upload selector dialog
FIX: category validation in composer was still using categoryName instead of categoryId
When creating a topic, don't select a category by default when allow_uncategorized_topics is false. Also, added category validation on the server to enforce allow_uncategorized_topics.
Only show filter button if the user has more than 2 posts
add current_user_provider so people can override current_user bevior cleanly, see

http://meta.discourse.org/t/amending-current-user-logic-in-discourse/10278
require dependency was leading to errors in dev