Changes:

World generation:

• Biomes are now generated differently.

Tiles:

• Added "magma" tile. Generates naturally around lava.
• Added "obsidian" tile. Generates naturally when lava meets water, instead of stone.
• Added "green", "blue", "purple" and "white" bricks along with a roof variant for each.
• "sand brick" now has a roof variant.
• Added "cactus planks" along with a roof variant.
• Added "cactus door".
• Added "blue flower".
• Modified all brick textures.
• If you destroy the bottom part of a tree or cactus the top part no longer brakes.

Wrench:

• Added "wrench". While holding it in the inventory right-click on a tile to rotate the tile.

• Added Zombie mob. 
• Left-click on it to remove it from the world.
• Spawns 100 zombies in each new world.
• This is just a test for future implementations of more mobs so the zombie does not have a function yet and just stands still but that will soon change.

Other:

• Destroying a ball will no longer cause the game to crash.
• Organized the inventory.