Add linux compatible simulator.

I made the simulator linux compatible (and hopefully Mac and Windows as well).
Most of the code is based on http://www.opengl-tutorial.org

I am using opengl 2.1, GLFW 3.0.4 and glm 0.9.5.3.

Once these libraries are installed, the code should compile with a simple `make` in the PopSimulator directory.
You can then start it with `dist/Debug/GNU-Linux-x86/popsimulator` from the PopSimulator directory (important so that it can find the shaders).
The makefiles have been generated by netbeans.