Merge pull request #1 from cocos2d/develop

Merging updates from base.
Merge branch 'develop' of https://github.com/cocos2d/cocos2d-html5 into develop
Multiline fixes on LabelBMFont: calculation for line break, empty lines handling, and first letter "swallowing".
Merge pull request #1714 from bassarisse/develop

cc.LabelBMFont issues