Most notably, we need to actually fix a bug in MSVC that doesn't know how to properly instantiate
enums in partial template specialization. There are more details outlined here:
http://stackoverflow.com/questions/15466594/why-does-msvc-fail-to-compile-this-template-function
The fix in this commit closes#10
Also in this commit is a hacky way to allow GL defines. Apparently "LoadImage" is defined as a
macro even with WIN32_LEAN_AND_MEAN. This means that we have to #undef the code that includes
it, meaning that we also need to make sure not to actually mix GLDefines.h with any file that needs
to use the functions from Windows.h
