minetest/minetest — pull request #1931 by Zeno- (2014-12-09 07:37:15+00:00)
Title: Increase performance of getLight() by approx. at least 100%

Leads to the following increases:
```
getSmoothLight() approx. 40% increase
getTileInfo() approx. 25% increase
MapBlockMesh::MapBlockMesh() 25-30%
```