Additions:

• added wrenches, which allow the player to rotate slabs
• added ladders, which can be used for climbing. After all, they just negate gravity
• added sulfur dust
• added the stone axe (mislabeled as "iron axe" in the commit title), which can be crafted from two sticks, a loose stone, and a rope in the merging table. It allows you to break wood.
• added ropes, which can be crafted from a stick, vines and tallgrass placed vertically in the middle of the handcrafting UI
• added vines
• added the handcrafting UI, which can be accessed by pressing L
• added sulfur lakes, which currently are the only way of getting sulfur on survival

Changes:

• furnaces need to be lit up by torches or firestrikers
• the player is now able to place blocks on the first block of a chunk
• torches cannot be placed on downwards-facing slabs (although they don't disappear when a slab is rotated)
• lit furnaces have a nice burning animation, and emit light
• multiple resulting items can now be taken from crafting stations at one