Design changes for /questions. Made the title field blank for new questions.
Fixed typo.
Fixed top graphic in IE8 by switching to a "mobile last" approach.
CSS cleanup & deduplication.
New logo for SV. PNG optimized.
Removed the ribbon.
Header rewrite, round 1.
Header rewrite, round 2.
Replace caches_page usage with cache headers in non-beta environments.
Fix default page title.
Fix title on /issues + bold 'partially kept promises'
Remove rack-cache

- no longer using Dragonfly
- have varnish in production
Set RAILS_CACHE_ID to the current revision if available.

This will ensure unique etags/cache keys.
Add TODO about expand_cache_key.

[ci skip]
Rename config setting 'issue_editing_enabled' to 'read_only' + add a global info alert in admin.
Turn on read_only mode in production.
Removing beta from deploy config.
Turn off read only mode.
Make sure VoteInferrer picks the vote with the most representatives from the chosen cluster.

Representatives sometimes miss a vote even when they're present.
Never *ever* hardcode paths please, this leads to bad caching bugs.