Vector Additions

Vector2 now has the Scale(d) and Rotate(d)Around functions.
Scale makes the Vector2 have a length of l.
Scaled returns a copy of the Vector2 with length scaled to l.
RotateAround rotates the Vector2 around v by angle ang
RotatedAround returns a copy of what that Vector2 would be if it were
rotated around v by angle ang.
Merge branch 'develop'