Contant Gravity

Put the number of the gravity into a final variable for easy adaption
Docu

docu juiste plaats deze keer
Rename methodes
Revert "Rename methodes"

This reverts commit 4e69f19fa2f9fee40b22f573a325f8ffd032a668.
Merge pull request #5 from MathijsC/Movements

Movements