Port r2_R_sun and r3_R_rain to Linux

Закрыто xottab-duty запросил слияние github/fork/eagleivg/xd_dev в xd_dev

Created by: eagleivg

List of changes:

  1. Port r2_R_sun and r3_R_rain to Linux (Use engine internal types and implement matrix conversion func - maybe slower than glm or another library).
  2. Fixed buffer overflow on linux due mismath size of types (LPDWORD casting)
  3. Fix crash at exit on Linux - forgoten Ansel clean.
  4. downgrade requirements for SDL2 (for build on ubuntu 16.04)