PyMC3 is now named PyMC

Hi,
PyMC3 has been renamed PyMC. If this affects you and you have questions, or you want someone to direct your rage at I'm available! Do let me know how i, or any of the PyMC devs can help.

Ravin

P.S Ive made a PR to the readme as well pinning the install to the PyMC3 branch. Hope this helps