Release Name: 1.3.0

Notes:
Ruby/SDL binary, dll with ruby interpreter.


Changes:
Fix/Improve documents
Add constant SDL::NOFRAME
Add following methods
  SDL::Screen.update_rects
  SDL::Event2.pump
  SDL::Mixer.driver_name
  SDL::Surface.blit
  SDL::Mixer.driver_name
Fix following methods
  SDL.video_driver_name