Added a CONTRIBUTING.md file (issue #34).
Added a CONTRIBUTING.md file (issue #34).

ngpestelos/chruby,JeanMertz/chruby-fish,JeanMertz/chruby-fish,kbrock/chruby,regularfry/chruby,kbrock/chruby,regularfry/chruby,ilikepi/chruby,ngpestelos/chruby,postmodern/chruby,rstacruz/chruby-fish,eunomie/chgo,eunomie/chgo,ilikepi/chruby,postmodern/chruby,rstacruz/chruby-fish