Stygian End Continuation

Essential

Updating EntityEndSkeleton

Added 3 items

Features

Add EndGrass Spreading

Add a BoneMeal for EndGrass

Add a creative tab for the mod

Add frequency configuration for valcanos

FIXE

• Fix #18
• Fix #16
• Fix #15

Fix 4 cascading worldgen , 2 remains in CanopyStructrue

Make optimization

Make biome larger

Revert optimization , make sometimes bug during worldgen

Reduce bottleneck in some classes

[From the official]

• Fix #19 by merging this pull request #21