Bumped to 1.21 and Java 21. Might add new stuff soon

Updated compatibility so this Jar will work with any version from 1.13 and above

- Fixed various problems
- Added command suggestion/tab completion feature
- Compiled with latest Java 17 version

GWEN

• Fixed Gwen animation having a broken offset
• Made the explosion during the Gwen animation no longer do damage to surrounding entities
• Fixed strange guardian jitter during the animation as well as making it more closely resemble the original Gwen animation

YINYANG

• Fixed the broken items, which now actually spawn on the player's head
• Fixed the blocks not spinning around the player

No changes, only updated to 1.17

Removed usage of several deprecated/outdated methods relating to armor stands, removed MC version detection 1.8 stuff. This version is ONLY for 1.16.5+