Improvements

• fix post/updateScene whose behavior wasn't predicable since the migration of the postprocessing nodes.
• post/builder: add useInput1OuputBuffer param, in order to define which render target from second input is used.
• ensure clonedStates are updated when inputs count is changed: Previously, the merge node input connections would not reflect correctly if the inputs are cloned or not, if more than 4 inputs where added to it.

Editor Update

• cop/image: add matcap presets.
• add several examples for simple material.
• comments and param labels do not overlap anymore in the network panel.