implement Vector interfaces

squashed commits:

added Vec2 classes

adding threshold of .001 for floating point vector comparisions

fix @Override annotations

adding vec3 classes

implementing hashCode methods

fixing style

remove redundant casts

adding serialVersionUID

fix getMinAxis and getMaxAxis

use flow math epsilons

use flow math compareTo

remove rounds from conversions to lower precision

implement toVector3

make get{Max,Min}Axis more efficient