Added wait to the Container class documentation.
Added wait to the Container class documentation.

The container class documentation did not automatically document the `Container.wait` method.

Signed-off-by: Andreas Backx <b15c342f1de186996bcca5e1a23cd684d2fadb32@backx.org>
vpetersson/docker-py,funkyfuture/docker-py,funkyfuture/docker-py,vdemeester/docker-py,vdemeester/docker-py,youhong316/docker-py,youhong316/docker-py,docker/docker-py,docker/docker-py,vpetersson/docker-py