Merge pull request #957 from ShengxiangChen/issue2261_LoaderBug

fixed #2261: Preload function failed in iOS 5.1.1
fixed #2264: added Version release note to changelog, and changed version number.
issue 2264: updated sapmales commit ID
HTML5 Audio pause and stop API is different from Cocos2d-x and JSB
HTML5 Audio pause and stop API is different from Cocos2d-x and JSB
HTML5 Audio pause and stop API is different from Cocos2d-x and JSB
Merge pull request #961 from ShengxiangChen/issue2220_audioBug

fixed #2220 : HTML5 Audio pause and stop API is different from Cocos2d-x and JSB
Merge pull request #960 from linshun/iss2264_v2.1.4

fixed #2264: added Version release note to changelog, and changed versio...
fixed #2267: synced input flags to latest CocosBuilder
Merge pull request #962 from linshun/iss2267_updateflags

fixed #2267: synced input flags to latest CocosBuilder
issue #2264: updated changelog
issue #2264: upated changelog
issue #2264: update samples commit ID for Node and tile auto tests.
fixed #2268: fixed director scene index of replace scene
Fixed #2269 fixed a bug of LabelTTF that setString is invalid when call setString("")
Merge pull request #963 from dingpinglv/Iss2269_FixBugForLabelTTF

Fixed #2269 fixed a bug of LabelTTF that setString is invalid when call setString("")
fixed #2269 Switch shader of cc.Sprite when call setTexture(null)
Merge branch 'develop' of https://github.com/cocos2d/cocos2d-html5 into Iss2269_FixBugForLabelTTF
Merge pull request #964 from dingpinglv/Iss2269_FixBugForLabelTTF

fixed #2269 Switch shader of cc.Sprite when call setTexture(null)
fixed #2144 fixed a bug of cc.ParticleSystem that the _totalParticles is wrong on canvas mode.