Make jruby optional until travis fixes rubygems
Fix a configuration bug that excluded jruby completely
Travis fixed their issues, jruby is mandatory again
Merge remote-tracking branch 'upstream/master' into super-admin

* upstream/master:
  Travis fixed their issues, jruby is mandatory again
  Fix a configuration bug that excluded jruby completely
  Make jruby optional until travis fixes rubygems
  Reverted mongoid generator for to use config/database.rb instead of config/database.yml.
  Defaulted all ORMs that used the mysql gem to use mysql2 when the options mysql and mysql2 are used and to force the mysql gem only when mysql-gem is specified in the generator.
Merge branch 'super-admin' of github.com:WaYdotNET/padrino-framework into super-admin

* 'super-admin' of github.com:WaYdotNET/padrino-framework:
  Improved the message shown after adding the admin to an app to tell the user to use `bundle exec rake db:migrate` and `bundle exec rake db:seed` to match the new way of specifically load tasks