Java Edition 12w30c

12w30c was released to fix some of the bugs and crashes in the 12w30a and 12w30b snapshots.

Fixes
5 bugs fixed


 * Fixed piston block animation bug
 * Fixed rain particles in certain biomes
 * Fixed Mob Spawners set to spawn FallingSand entity crashing the game
 * Fixed minor text bugs
 * Fixed portal placement