1. add assert condition of rendering when adding command
2. fix bug: renderTexture->SpriteRenderTextureBug
change assert message
closed #4761. fix a compile error
Merge pull request #6242 from andyque/fix_zfighting

fix a compile error
adjust comment
Merge pull request #6240 from dabingnn/develop_add_rendererAssert

Trigger an assert if a command is added while render is rendering.
Warning fixes in ui, getZOrder -> getLocalZOrder
Merge pull request #6244 from dumganhar/develop

Warning fixes in ui, getZOrder -> getLocalZOrder
Solve the incorrect effect of some transition test case in lua-tests.
Merge branch 'develop' of https://github.com/cocos2d/cocos2d-x into develop