Added mixins
Code refactoring, cheated a lot to stick to those 30 lines...
Slight changes in forward declarations
Updated license header
Renamed mixin method to with
Added assertion upon an attempt to include a mixin
Lame hacking to stick to that 30lines mantra
Fixed assertion error message
Updated README as of v0.5.0 changes
Updated quicktour
Pushed clean source
Pushed mixins specs
Pushed 0.5.0 rockspec
Updated version_history as of v0.5.0 changes