Allow users to override the RAILS_ENV and RACK_ENV in Passenger
Added 'ruby_in_development_mode' function to Ruby SDK
Disable 'rake assets:precompile' when Ruby in development mode
Skip 'bundle install' when development mode and the Gemfile was not modified
Disable Ruby cartridge stop/start when in development mode
Make sure httpd is in the right environment
Disable bundler when in development mode and the Gemfile is not touched
Update cartridge_guide to explain Rails development mode
Updated cartridge_guide to mention DEBUG env variable for Django