fix bugs & migrate to swift4
move wrapper out of Infinity
Merge pull request #17 from Jauzee/master Merge jauzee/Infinity to DanisFabric/Infinity
add animatorOffset for PullToRefresher which can adjust the position … …of animator
删除contentInsetType的设定，过于累赘，意义不大
优化接口
change enableXXX to isXXXEnabled
optimize gif animator
version2.0.1