added ability to use darkfish-rdoc if installed.
added ability to use darkfish-rdoc if installed.

tmornini/rake,pjump/rake,mat/rake,bentley/rake,askl56/rake,ipmobiletech/rake,envato/rake,envato/rake,utilum/rake,88rabbit/rake,hsbt/rake,taiganakagawa/rake,mat/rake,jaustinhughey/rake,Vanzct/rake,hsbt/rake,codedogfish/rake,ruby/rake,ruby/rake,zzak/rake,esasse/rake