v1.3.0-rc1

• Added new platforms
  • Windows
  • Linux
• Graphics
  • Added CompositeMode to change composite mode (e.g. masking or additive drawing)
• Audio
  • Moved from exp/audio to audio: No more experimental package!
  • Changed APIs (almost fixed)
  • Added audio/vorbis to decode Ogg/Vorbis stream
  • Added audio/wav to decode Wav stream
• Others
  • Made most of functions concurrent-safe
• Bug fix