Created new file named Global.Java

+ Created new file Global.java
* Extracted most String Literals from across the project into one file.

-- I just think it would be easier to consolidate all commonly used Literals to one file, to increase efforts.
If this new PR gets accepted, change it to whatever you feel is right. I'm just adding this as a concept. Why have two "SpongeModAPI", when you can have class.SpongeModAPI? That's why I did this.