Merge branch 'master' of https://github.com/BSVino/MathForGameDevelopers

Tests of different integration techniques

Semi-implicit Euler

Euler integration, fixed and variable

Merge pull request #6 from gemorin/master

chdir back to previous dir after glfwInit() on macOS

Constant speed splines

Composite simpson's rule

Fix for VS 2015 that hopefully doesn't break 2010

Cubic spline

Fast inverse square root

Cubic interpolation

Seaweeeeeeed omg

Mac port pretty much finished. Hopefully didn't break Windows.

Some attempts at getting the OSX port to work, but no deal.