Renamed ScoreBehaviour to GUIBehavior

Changed the name of Score behaviour to reflect the changed nature of
the script.
Partial functionality for a shot-power meter.
Merge pull request #41 from KodeAndGame/Add-Turbo-Button

Added Turbo Functionality
Made changes needed for merge
Merge pull request #40 from KodeAndGame/Variable-Shot-Power

Renamed ScoreBehaviour to GUIBehavior
Merged master into this branch