issue #2970:crash for CCLabelTTF when setting dimension width less than the font height
Merge branch 'develop' of https://github.com/cocos2d/cocos2d-x into developLabelTTF
Merge pull request #4037 from samuele3hu/developLabelTTF

issue #2970:crash for CCLabelTTF when setting dimension width less than the font height