Remove pointless Message Task

CraftBukkit supports asynchronous messaging.

Why not make use of it?
Remove pointless If statement

The for loop inside of it already checks this condition
Make the package checker run asynchronously

Because why would you do it any other way?
Thread executors are thread safe. Don't waste the main threads time.
Use a LinkedHashSet for fast .contains(Object)
Create a single static Pattern which covers all replacements

Also ignores case :D
Remove == comparing strings

Using == to compare strings is unsafe and can result in unexpected
behaviour.
Merge pull request #6 from ShadowDog007/master

Performance improvements + random fixes