Make the composer and TopicCreator use category id instead of category name

Also fixes #1171
Added backwards compatibility for topic creation
PNG Files optimization
ready for heroku
remove public/assets from git ignore
add mailchimp settings to production.rb
remove assets from git
Update client.zh_CN.yml
Extracted nickname registration into a private controller method
add a site setting for allowing animated avatars
Merge pull request #1372 from ZogStriP/site-setting-for-allowing-animated-avatars

add a site setting for allowing animated avatars
Enum site settings can have translatable names in dropdown. Add setting for how often users get digest emails by default: default_digest_email_frequency.
Version bump to v0.9.6.1
Merge branch 'master' of github.com:LaunchAcademy/discourse
Merge branch 'master' into heroku
update gemfile lock
Explicitly set username for Octokit
fix merge conflict
add second argument for team authenitcation
more fixy