Update README.md
Merge pull request #33 from yuvadm/hard-order

Implement hard order values
Allow using custom primary keys on models.
Merge pull request #34 from kjagiello/master

Allow using custom primary keys on models.
Added template to setup.py
Merge pull request #36 from defeo/master

Added template to setup.py
Merge pull request #31 from aztrock/patch-1

Update README.md
Ship 0.4.0

Fixes #37, #20
Merge pull request #38 from bfirsh/ship-0.4.0

Ship 0.4.0