Remove methods for updating logs out of User
spec code added
Activity clearing properly
Move discussion feature added
refactor descriptions, add markdown buttons to discussion descriptions
Generate usernames for names with non-ASCII characters

Add migration to update all usernames

Remove unecessary filtering in generate_username

Keep current username when appropriate
Truncate usernames to 18 characters without suffix - fix #637
expands fixed width on button, fixes #643
fix markdown dropdown css