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.
Mipmap generation for DXT textures.
Mipmap generation for PVRTC compressed textures.
Fixed crash when changing the value of a processor parameter.
Fixed Dll lookup in MGCB to look in executable path.
Updated from previous merge
Added Accelerometer.cs support to main branch, merged from Android and iOS branches
Merge pull request #1645 from SickheadGames/GenerateMipmaps

DXT and PVRTC Mipmap Generation
Merge branch 'develop' into effectopt
Merge pull request #1660 from SickheadGames/effectopt

Effect Memory Optimizations
Merge branch 'develop' into develop.portable