debug option directly added to makefile
Formatted FactorySystem

now in namespace; Sigma::FactorySystem
added comments
Merge remote-tracking branch 'upstream/develop' into formatting
Merge remote-tracking branch 'upstream/develop' into formatting
formatted IGLComponent.h

mostly just new comments. it is an interface, after all.
global replace of \returns to \return
GLMesh changes

minor changes for formatting and comments, GLMesh is now in Sigma namespace, etc.
most significant change has to do with shaders. Instead of a reference to the static GLIsoSphere shader, each
GLMesh may reference a different shader using mesh.LoadShader(name).
Merge remote-tracking branch 'upstream/develop' into formatting

Conflicts:
	src/systems/OpenGLSystem.cpp
refactored GLIcoSphere

properly uses inherited properties from GLMesh. Refine() is refactored to be much easier to read.
None of the functionality of this class has changed.
simplified GLIcoSphere's vertex normal computation

it's a sphere - no need to mess with adjacent faces. all normals are in the
same direction as the vertex itself!
assets folder re-included
Formatting for GLCubeSphere

Biggest change is that GLCubeSphere is now a subclass of GLMesh.
Other than that, there is a lot of commenting, formatting, and
consistency-making.

known bug(?) using assets/mars as the cubesphere texture shows up
as a big purple planet.
Merge remote-tracking branch 'upstream/develop' into develop
reduced mars image file size
addressing pull request issues, namely:

* minimal includes in header. no unnecessary includes
* Vector3f changed back to Vertex

Note that this still only applies to GLMesh, GLIcoSphere, and GLCubeSphere so far
Fixed an include issue with SOIL