Improve pipeline Light input

• Removed lights from RenderScene, replaced by a gather callback
• Removed SharedLight
• Moved light bounding sphere calculation to the GPU, reducing packed light size to 3 vec4s
• Updated pipeline guide

why rvalue reference?

Mostly because it is called like this:

mGpuLights.clear();
rc.onGatherLights(LightCallback{mGpuLights});
mSsboLightData->bind().setData(mGpuLights, GL_STREAM_DRAW);

changed this line in version 2 of the diff

added 1 commit

• 45158ef5 - Use a regular reference for LightCallback

Compare with previous version

mentioned in commit 5921cb6d

merged