Ensured SPE.Group.transparent value is assigned properly.
Asteroid alpha example
Enabled SPE.Emitter#alive to determine the percentage of particles alive at any given time.
Merge branch 'dev' of github.com:squarefeet/ShaderParticleEngine
Merge branch 'master' of github.com:squarefeet/ShaderParticleEngine into Editor
Fixed accelSpread bug. Added PopupWindow system. Added beta 'export' function. Added beta 'new' function.