Merge pull request #6 from pschwartau/master

Ability to use complex expressions in joins
Version 0.1.7
Development continues
Add support for ORDER BY x NULLS FIRST / LAST
Merge pull request #8 from ulle/master

Add support for ORDER BY x NULLS FIRST / LAST
increasing minor version to 0.2.0 because of possible breaking changes by ordering
development continues
added support for auto_increment columns