Remove ActiveSupport dependency

Inlines ActiveSupport methods #classify, #underscore, and #constantize
Includes related tests from ActiveSupport.
Forgot to add test cases in previous commit
Merge pull request #21 from hybridgroup/remove_activesupport

Remove ActiveSupport dependency
Merge branch 'master' of https://github.com/hybridgroup/artoo into documentation
Adding documentation for classes in root dir
Adding sinatra-yard option for methods sinatra like syntax