Convert the glow effect to support stacking
Convert the glow effect to support stacking

This involves the following:

- Removal of the u_sampler2 uniform which is no longer needed since corresponding texture
can be accessed via cc_PreviousPassTexture.
- Conversion of the GLSL to use cc_PreviousPassTexture.
- Removal of the first render pass since effects are no longer responsible for rendering CCEffectNode's
children into an FBO before the interesting work starts.
- Removal of the code from the last pass that drew the resulting image into the displayable frame buffer
since effect's are no longer responsible for that work either.

dnessorga/cocos2d-objc,cogddo/cocos2d-objc,liduanw/cocos2d-objc,TukekeSoft/cocos2d-spritebuilder,TukekeSoft/cocos2d-spritebuilder,dnessorga/cocos2d-objc,knight2010/cocos2d-objc,finthamoussu/cocos2d-objc,codepython/cocos2d-objc,savysoda/cocos2d-objc,yaoxiaoyong/cocos2d-objc,DNESS/cocos2d-objc,nader-eloshaiker/cocos2d-objc,cocos2d/cocos2d-objc,savysoda/cocos2d-objc,richardgroves/cocos2d-iphone,lpeancovschi/cocos2d-objc,DNESS/cocos2d-objc,yaoxiaoyong/cocos2d-objc,nader-eloshaiker/cocos2d-objc,cocos2d/cocos2d-objc,dnessorga/cocos2d-objc,seem-sky/cocos2d-swift,zaneLou/cocos2d-objc,tambarskjelve/cocos2d-objc,lpeancovschi/cocos2d-objc,finthamoussu/cocos2d-objc,knight2010/cocos2d-objc,TukekeSoft/cocos2d-spritebuilder,yaoxiaoyong/cocos2d-objc,lpeancovschi/cocos2d-objc,liduanw/cocos2d-objc,savysoda/cocos2d-objc,dnessorga/cocos2d-objc,seem-sky/cocos2d-swift,seem-sky/cocos2d-swift,nader-eloshaiker/cocos2d-objc,liduanw/cocos2d-objc,TukekeSoft/cocos2d-spritebuilder,DNESS/cocos2d-objc,finthamoussu/cocos2d-objc,seem-sky/cocos2d-swift,richardgroves/cocos2d-iphone,SuPair/cocos2d-objc,DNESS/cocos2d-objc,zaneLou/cocos2d-objc,SuPair/cocos2d-objc,oxeron/cocos2d-objc,cogddo/cocos2d-objc,tambarskjelve/cocos2d-objc,cogddo/cocos2d-objc,liduanw/cocos2d-objc,dnessorga/cocos2d-objc,nader-eloshaiker/cocos2d-objc,zaneLou/cocos2d-objc,cogddo/cocos2d-objc,oxeron/cocos2d-objc,savysoda/cocos2d-objc,zaneLou/cocos2d-objc,SuPair/cocos2d-objc,knight2010/cocos2d-objc,yaoxiaoyong/cocos2d-objc,SuPair/cocos2d-objc,yaoxiaoyong/cocos2d-objc,knight2010/cocos2d-objc,SuPair/cocos2d-objc,tambarskjelve/cocos2d-objc,finthamoussu/cocos2d-objc,codepython/cocos2d-objc,richardgroves/cocos2d-iphone,liduanw/cocos2d-objc,lpeancovschi/cocos2d-objc,codepython/cocos2d-objc,tambarskjelve/cocos2d-objc,codepython/cocos2d-objc,DNESS/cocos2d-objc,tambarskjelve/cocos2d-objc