Wp8 v3 rendertexture fix

I looked at the CCRenderTexture.cpp code and found this around line 249:

        if (Configuration::getInstance()->checkForGLExtension("GL_QCOM"))

What is the GL_QCOM extension? Since this is not supported on WP8, I changed the line to:

#if CC_TARGET_PLATFORM != CC_PLATFORM_WP8
        if (Configuration::getInstance()->checkForGLExtension("GL_QCOM"))
#endif

This will allow the texture to be copied.

I also made changes to Cocos2dRenderer.cpp at line 72 to send the EVENT_COME_TO_FOREGROUND event.

There are still problems with the RenderTextureTests. Several tests are not listening for the EVENT_RENDERER_RECREATED event and are not recreating the sprites. Also, some of the rendertextures are not getting the EVENT_COME_TO_BACKGROUND/FOREGROUND events which seems to be a bug/bugs in the tests.