End City Revamp

**BETTER END CITIES:**End Cities have been tweaked and subtly redesigned to be more ornate and interesting. This also includes fixing a few bugs in vanilla generation, such as stair sub-sections not properly alligning or an eroniously-placed slab preventing access to the large tower via the spiral 'staircase'.

GRAVITY HAMMER:
A brand new weapon (repairable with Shulker Shells!) found in End Cities, with several unique new abilities:
• Left-click deals damage and launches grounded mobs into the air.
• If the target is already in the air, instead launches them and refreshes ability cooldowns.
• If target has levitation, instead smash them down into the ground and gain slow-falling.
• Right-click (on the ground) causes all nearby entities (including the user) to levitate [15 second cooldown]
• Unless hit with a follow-up smackdown, non-player mobs gently glide to the ground afterwards.
• Sneaking players recieve reduced levitation, for greater control.
• Right-click in the air provides the user with a few seconds of slow falling [7 second cooldown]