IES Photometrics support and Beam Lens rendering improvements in Cycles

IES Photometrics import and assignments to spot light allows for more photo-realistic volumetric beam rendering. With this, more detailed beam lens settings has been added to allow further enhancing the rendering quality for beam rendering with gobo projection.

• Add support to import IES photometrics and apply them to beams in Cycles
• Allow changing beam lens diameter for Cycles, based on global or per fixture settings
• Set hidden objects as hidden also for renderer
• Make more items translatable, disable automatic translation for Fixture controls
• Add version checks on start for Python, Blender, and for the BlenderDMX Addon