Pocket Edition v0.13.0 alpha build 2

v0.13.0 alpha build 2 is the second build version released for v0.13.0.

Changes

 * Obsidian now breaks in 6.5 seconds rather than 3.
 * Minecarts now stack on top of each other.
 * Villagers now open doors of all kinds.

Fixes

 * The terrain doesn't flicker invisible anymore when too many chunks are active.
 * Fixed a crash when it's night in a village and you're holding a door not made of oak.
 * The held item's movement in first person is more fluid now.
 * Fixed mobs disappearing after going through a portal.
 * Removed redundant tripwire recipes.
 * Single pieces of redstone dust now only get powered from below.
 * Doors now pop correctly when destroyed by removing the block below them.
 * Mobs aren't pulled immediately back into minecarts after being thrown out.
 * Ocelot mob heads don't disappear anymore.
 * Block of redstone is now properly translated.
 * Fixed item duplication glitch in the anvil.
 * Fixed various redstone-related bugs and inconsistencies.
 * Fixed corrupted images in the language screen.