1. added TagAdapter and make it easier to create and edit TagViewGroup.
2. moved AnimatorUtils out of the library to make it clean.

add bounds checking when direction changed

fixed some bugs and optimized

1. fixed the bug that lines draw wrong when target sdk is less than or equal to 4.3
2. add animation Properties

1. add CircleInnerRadius property in animation.
2. fixed some bug

add getter and setter methods