Merge branch 'feature.lazy-loading'

Thanks to @mmerickel for working on making lazy loading for settings
work again. I hereby eat my words of it not being supported.

This fixes backwards compat with pyramid_mako 0.2 again.

Closes #12.
Prep for 0.3.1
Merge branch 'master' into feature.renderer-relative-paths

Conflicts:
	CHANGES.txt