Particles expose absence of lighting information

[kpreid]

When a block is destroyed, the particles left behind may access "empty" areas of the lighting array, resulting in black particles.

Possible fix: We should either temporarily or permanently let the empty air have light data, so that moving objects (these particles, and eventually bodies) can be properly lit.

Adding fallback lookups in the texture shader would not help; consider the case of destroying a lone block in midair.