CCTextureAtlas::updateQuad update according to review comment

set "m_bDirty = true" directly in CCLabelAtlas.cpp and
CCTileMapAtlas.cpp

Signed-off-by: Yongqin Liu<liuyq0307@thundersoft.com>
Merge branch 'master' of https://github.com/liuyq/cocos2d-x

Conflicts:
	cocos2dx/label_nodes/CCLabelAtlas.cpp
	cocos2dx/tilemap_parallax_nodes/CCTileMapAtlas.cpp