Java Edition 13w39a

13w39a is the eighth snapshot released for 1.7.2.

Additions

 * Added red sand
 * Generated on the lowest surface levels of the mesa biome
 * Behaves like normal sand
 * Can be smelted into glass and crafted into TNT, but cannot be crafted into sandstone
 * Added minecart with command block
 * Can only be obtained using /give (item ID 422 or minecraft:hopper_command_block) or /summon (entity name MinecartCommandBlock)
 * Activated by activator rails
 * Run their command every so often as long as they are powered - Running a command block minecart across a single powered activator rail at full speed will run its command thrice
 * Can be success-tested while on a detector rail with a redstone comparator next to the rail (just like how the minecart with chest and minecart with hopper can be fill-checked)

Changes

 * Orange stained clay generates in mesa in place of sandstone
 * When enchanting books, books can now gain multiple enchantments.
 * Logging is now done using Log4j 2
 * Default logging location is now in logs/latest.logs, older logs are archived in logs/2013-09-23-1.lg.gz, with the number at the end increasing each startup
 * Thanks to Log4j 2, the way logs are saved can be changed, examples: html page, database, errors only, no logging at all

Fixes
9 bugs fixed

From released versions before 1.7
 * – Sky/lighting doesn't get darker during a thunderstorm
 * – Villagers act like it is raining when they are in the desert, and it rains elsewhere
 * – The saddle equip sound effect does not play when equipping a pig with a saddle.

From the 1.7 snapshots
 * – Rain doesn't make particles/sound in some biomes (extreme hills)
 * – Snow golems die in extreme hills snow
 * – XP orb sound bug
 * – Enemy Monster slider controls the sound of items entering one's inventory

From the previous snapshot
 * – Hopper:
 * – Hopper: