Merge branch 'develop' of https://github.com/ufo22940268/DropRefreshView
Add loading sign.
Add loading icon.
Add loading icon.
Update reademe.
Merge branch 'develop' of https://github.com/ufo22940268/DropRefreshView into develop

Conflicts:
	demo.apk
Merge branch 'develop' of https://github.com/ufo22940268/DropRefreshView into develop

Conflicts:
	demo.apk
Merge branch 'develop'

Conflicts:
	README.md
	slide2.gif
Merge remote-tracking branch 'origin/master'