Made dummy-app in /spec compatible with rails 4
Added rails 4 version to appraisals
Added rails 4 gemfile to travis config
Removed ruby 1.9.2 for rails 4 (it requires 1.9.3 or higher)
Update travis config

Attempt to fix 1.9.2 Rails 4 exclusion. Remove branches and email details.
Add Ruby 2.
Kill Rails 4 deprecation warnings

As many as possible, anyway. The secret_key one will still happen.
Bump patch versions of Rails 3.x
Stop cache_control warnings

Handled by Rack now.
Eager load in test environment

Trying to fix the broken CI build...
Update readme [ci skip]
Update gitignore with new ruby version files
Update readme

Adds note about new config options.