Merge pull request #54 from neavo/master

update maven to v0.2.0
DrawTask: live-danmakus issue fix
update README.md
NativeBitmapFactory: support api-21
DanmakuTextureView: enable Hardware-Acceleration at initialization
v0.2.1
DrawHandler:
DrawHandler: use mFrameUpdateRate instead of magic-number
DrawHandler: fix some update issue if mUpdateInNewThread == false
Merge pull request #5 from ctiao/master

sync