Add base files for the library

Most code is taken from Beatshot, which will be my first project
utilizing this module library
Add Artemis Source

we're going to be providing libGDX specific optimizations to it,
allowing for better project integration.  This project is strictly a
libGDX submodule, so we do not have to worry about the code being
generic
Make use of some libGDX based utils
Allow selecting entities that only belong to multiple groups
Add component that represents a path, and allow entities to follow along it