Added the basic header file for the project.
Added BA/Common.hh, a set of common declarations projectwide
Added BA/Platform.hh, a collection of platform-specific inclusions
Added header file for Scene class.

Scenes contain the global rendering context ("GlobalState") and the objects
to be rendered.
Added a global state object.

GlobalStates include information needed by the renderer.
Added Vector3, a class for 3D vectors.

Vector3 supersedes the bvec3 data structure from libbill (see etcetera/libbill)
and uses standard C++ functionality to implement vector math.
Added BObject, a base class for this project

BObject provides basic functionality to all classes within the system.
Added a tester for Vector3

This tester program tests the primary functionality of Vector3.
Merge branch 'master' of https://github.com/tnwae/bearded-axe