Update pubspec.yaml

Fix find renderObject is null

Update README-ZH.md

update readme for ZH

FORMAT CODE

update readme

Fix #19 update pub version

upload to pub and update version to 1.1.3

FIX #17 UPDATE VERSION TO 1.1.2,ADD NEW FEATURE

update readme

update version and publish to pub

UPDATE README

UPDATE README

Fix #11 #15

Merge pull request #14 from iChenLei/docs/changelog-order