Use a cached clone of the remote repository to speed up further builds.

This adds a top-level cache/ directory.
Each repository gets a bare clone in there, in sub-directories named with a hash of the repository URL.
Lock while running git fetch on cache directory.
Make sure cache directory exists
Fixed acceptance tests
Updated Gemfile
Added godfile (uses rackup for now).
Configure god.
Configure for Rainbows.
Initial Capistrano setup.
Make sure the directory Capistrano expects, exist.
Capistrano setup: Added missing stylesheets directory
Deploy via remote cache.
Custom migration task
Fix DB creation, shared DB directory
God configuration
Changed DB to mysql

Dropped DB link creation since we switched to MySQL.
Fixed service shutdown recipe
Make sure the builds, gems, and cache directories are properly created and linked during deploy.
Avoid threading for now. Setup for Github hooks. Fixed logging.
Added minimal security.