Warning: podenv already installed, it's just not linked

[MattMorgis]

Great tool! In light of this news, my team is finding podenv to be a great way to manage multiple versions of CocoaPods.

After installing podenv for the first time with homebrew, I tried to run podenv version and received the following message:

Warning: podenv already installed, it's just not linked

I overcame this by running

brew link --overwrite podenv

Going to submit an incoming PR to update the docs incase this happens to anyone else.