Docs are generated from master instead of latest stable
There's now a `stable` branch with corresponding docs. I will keep the `stable` branch pinned to the latest tag:

http://docs.peewee-orm.com/en/stable/

It looks like the documentation is generated against master instead of the latest stable release. I was looking at implementing ManyToMany and noticed I couldn't import the `ManyToManyField` which is mentioned in the docs. A quick look at the latest commits show that this is added after the 2.4.5 release. It's a bit confusing as the page title of the documentation mentions that 2.4.5 version.

Mentioned at these two pages:
http://peewee.readthedocs.org/en/latest/peewee/querying.html#manytomanyfield
http://peewee.readthedocs.org/en/latest/peewee/playhouse.html#ManyToManyField
