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

Also fixes #1171
Added backwards compatibility for topic creation
Use Discourse.Resolver to load mobile templates when they exist
Detect whether to use mobile view. Session var mobile_view can override automatic detection.
Create a mobile css manifest
Store mobile flag in Discourse.Session instead of Discourse
Restructure the app/assets/stylesheets directory
rename application.css.erb to desktop.css.erb
Add link in hamburger menu to switch between mobile and desktop views
FIX: Index out of range error

Fixes 'index out of range error' that occurs when viewing a user's
profile page when they haven't yet posted a reply or created a topic
and is @mentioned in a topic.
Add span.btn-text around 'Reply' text in the post menu
Restructure login form for mobile
If mobile view, don't switch to small logo in the header when scrolled down in a topic
new mobile styles, some structure changes
Hide flag modal while flag is submitted
adding missing files back in
Add cancel button to delete replies dialog
Merge branch 'master' into mobile
Merge branch 'mobile' of https://github.com/awesomerobot/discourse into mobile
JSHINT: missing comma