Updated C++MathLibrary to v1.1

Change log:
- Added Matrix4x4.h & Matrix4x4.cpp:
- Added the following new function to Matrix4x4:
- static Matrix4x4 Ortho(...)
- Added the following new functions to Vector2:
- float AngleDeg(...)
- float AngleRad(...)
- bool operator==(...)
- static Vector2 Scale(...)
- static Vector2 Max(...)
- static Vector2 Min(...)
- static void Lerp(...)
- static float Distance(...)
- static float Angle(...)
- void Set(...)
- float& operator[](...)
- std::string ToString() <--- Temporary