R&D rendering Directional Light Maps with Blender's Cycles

[BinToss]

These won't be faithful to Halo's Tool-based light maps the way OS_Tool's light maps are (because it's a modified Tool.exe), but this might help with accuracy and time costs while improving quality.

There is a multi-threaded-rendering patch for Tool, but I'm unsure if it affects the DLM pipeline.