fixed gamma correction on particles
fixed dynamic blend change
Merge pull request #70 from guycalledfrank/particle-system-fixes

Particle system fixes
FIX gamma correction for particles
Update physics example to latest version of ammo.js
Update README.md
[RELEASE] v0.158.8
[VERSION] v0.159.0-dev
Merge pull request #15 from playcanvas/master

merge