The call to readlink -f fails on OS X (and probably other bsd's) rendering this plugin ineffective on my mac. This pull cleans up the plugin using git rev-parse --show-toplevel instead which works well on both linux and osx.
git rev-parse --show-toplevel
It also cleans up some of the variable to keep prompts clean.
remove readlink call and clean up
(this is for the virtualenvwrapper plugin, if that wasn't clear :-) )
Merge pull request #1173 from walkah/virtualenvwrapper-osx-fix
Readlink is different on OS X