Close #48 : Ubuntu support

* SHELL variable added or else bash colors doesn't work
* bundler installed from gem, because apt-get ruby-bundler doesn't work
Close #49 : OSX Support

* rb19-bundler added to macports
Close #50 : Check if .makerc exists

* Added target "checks" for futher checks
* Added check if .makerc exists
Fixes #46, Fixes #48 : No docs and ri for bundler gem