Update Util.java

Removed the redundant 'number' variable
Update README
Rename RapiidEngine.iml to Rapiid_Plugin.iml
Update plugin.yml

Changed name to Rapiid_Plugin
Update BlockListener.java

Added code description
Update PlayerListener.java

Newline at end of file
Update FireworkEffectPlayer.java

Newline at end of file
Update EntityListener.java

Added code description
Update Main.java

Added code description
Update PlayerListener.java

Added code description.
Commented out the 'butcher' function, since it's not finished yet.
Merge branch 'dev'