adds implicit class JVector3Ops to math.Vector3 object

Because libgdx makes rampant use of final vector3s subclasses of their
classes can't make use this nifty new math.Vector3. adding an implicit
class that has some of the nice methods should work around that
adds implicit class JVector2Ops to math.Vector2 object

a workaround for the use of final vector2 in libgdx source
Merge branch 'math' into graphics