BaseDanmakuParser: add getTimer() method
BaseDanmakuParser: parser() changed to protected abstract && parse() is replaced by getDanmakus()
DanmakuFactory: add updateSpecicalDanmakuDuration and resetDurationsData
CacheManagingDrawTask: refactor CacheHandler
IDisplayer: correct slopPixel calculation for the machine with low density and high resolution
AndroidDisplayer:fix failure of anti-aliasing caused by clearShadowLayer