Added bloom post process.
Fixes #38, gaussian blur together with bloom now working. Temporarily disabled branching of thunder bolt due to some bug.
Merge branch 'bloom'

Conflicts:
	datx02-rally/datx02-rally/Particles/WeatherSystems/ThunderBoltGenerator.cs
	datx02-rally/datx02-rallyContent/datx02-rallyContent.contentproj