Direction

Make setDirection work modulo( 2*PI )
Docu constructor, name rules
More docu
More docu and minor changes

Kijk zeker nen keer na ;)
Defensive methods
Docu
Revert "Docu"

This reverts commit 45eee71f0445628651032485eb352ec2ccc38b27.
Merge pull request #3 from MathijsC/Existence

Existence