Removed unused non-XNA method Effect.End().
Made the Effect collection classes immutable.
Changed all Effect classes to use arrays to save memory over List<>.
Added EffectParameterCollection.Empty and EffectAnnotationCollection.Empty which saves alot of memory.
Merge branch 'develop' into effectopt
Merge pull request #1660 from SickheadGames/effectopt

Effect Memory Optimizations
Merge branch 'develop' into stable_BtA