Invisible Lighting

Adds invisible blocks that emit all 15 light levels and are craftable in survival. Great for modpacks that have lots of building involved and modded SMPS.
All of the light blocks are crafted starting with light level 1. It is crafted with a single glass bottle, iron nugget, and glowstone dust. The rest are crafted with a single glowstone dust and the level before the one you are trying to craft.