Merge pull request #1 from ufo22940268/develop

Optimize animation.
Merge pull request #2 from ufo22940268/develop

Develop
Merge branch 'develop'
Update download link.
Update gif.
Merge pull request #4 from ufo22940268/develop

Develop
Merge branch 'develop' of https://github.com/ufo22940268/DropRefreshView
Merge branch 'develop'

Conflicts:
	README.md
	slide2.gif
Merge remote-tracking branch 'origin/master'
Make path more smooth, fix restore issue.