Documentation + Fixes / Cleanup

[Col-E]

What's changed:

• Added documentation to a few classes.
• Rewrote vague documentation in a few instances.
• Removed redundant code such as myBoolean == true and myBoolean = false in constructors.
• Minor formatting and code cleanup in a few classes.

What's fixed:

• Grass and dirt textures were not properly merging due to the world rewrite. Now looks as it did before the re-write.
• Proper resource closure in ModLoader.
• Proper resource closure in WorldProvider.
• Corruption BG not reaching the bottom of the screen.
• ConcurrentModificationException thrown if entity.die() was used, now fixed.
• maxAI used by Enemy was static, but was set to unique values in different enemy implementation constructors.

[egordorichev]

Thank you!