v3.0.16

1. onPageChanged not fired in Landscape (IOS)
2. draw the page with different size to center
3. support the page with rotation

v3.0.15

1. fix iPad scale offset problem
2. add code protection to avoid crashes

v3.0.14

1. fix in iPad can not zoom problem(offset still has problem, but zoom works)

v3.0.13

1. fix in iPad layout not center problem

v3.0.12

1. fix source.expiration check

v3.0.11

1. improve iOS zoom, can zoom from pinch center
2. fix call setState on an unmounted component

v3.0.9

1. use CATiledLayer to improve iOS render performance

v3.0.8

1. use await to unlink file
2. fix podspec
3. do not count a scrolling gesture as a tap

v3.0.6

1. add cache file expiration
2. enhanced file download stability

v3.0.5

1. OnError return Error() object
2. fix cache overwrite error
3. add Android content:// support
4. fix type error
5. Refactor view.propTypes to ViewPropTypes.