Update AWD2.1 + AssetEvent + bugfix

next update 2.1
added AssetEvents for ShadowMapMethod and EffectMethod

if the last AWDBlock of a AWDFile is a TextureBlock, the parser will through a Error at
ParserBase.as line306. 
This happens because the parserBase.as tries to execute _Timer.start(), while _timer is not defined anymore.
For now i just added the test - if _Timer exists -, but i do not know if this might not end up with trouble in other parsers etc.