Add a text field in the example.
Update README.md
Update README.md
Fix a small bug: " [self.enterUsername.text length] > 0"
Remove UITextField in storyboard.
Update the directory of YO.h
Update README.md
Updating to iOS 8 SDK
Update README.md
Update README.md
Update Demo UI.
Merge remote-tracking branch 'origin/master'
Add the screenshot
Update README.md
Add the screenshot
Merge remote-tracking branch 'origin/master'

qin/YO-iOS-SDK

# Please enter a commit message to explain why this merge is necessary,
# especially if it merges an updated upstream into a topic branch.
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# the commit.
Update README.md
Merge pull request #2 from yiqin/master

Update