Starting in on docstring, comment and code cleanup.
More cleanups.
Continuing cleanup
Starting work cleaning up query classes.
Just a few more docstrings.
A few small updates to transaction & savepoint.
Doc change for readability
Composite foreign key for composite pk
Adding some new to-dos
Doc conf.
Add a missing property copying in Node.clone.
Merge pull request #272 from xiaq/master

Add a missing property copying in Node.clone.
Removing composite FK for now.
Adding validation to ForeignKeyField `rel_model` attribute.
Moving `Proxy` into peewee.
Doc updates.
Adding proxy to exports.
Moving proxy tests.
Adding support for proxy foreign keys.
Changing fk SQL generation code.