Update Jruby-rack and force use of Jruby::Rack::ErrorApp
Remove features and edit tags controller
Merge pull request #914 from JamesGlover/return_503_when_busy

Update Jruby-rack and force use of Jruby::Rack::ErrorApp
Merge pull request #915 from JamesGlover/cleanup_unused_features

Remove features and edit tags controller
Merge updated Gem versions