continued implementing Ray3D class

Signed-off-by: Marcel Schwittlick <marzzzel@gmail.com>
added a couple of functions:
- subSelf
- hashCode
- invert
- interpolateToSelf
- limit

Signed-off-by: Marcel Schwittlick <marzzzel@gmail.com>
refactoring some fields

Signed-off-by: Marcel Schwittlick <marzzzel@gmail.com>
added barebones of VecMathUtil class

Signed-off-by: Marcel Schwittlick <marzzzel@gmail.com>
implemented Line3D

Signed-off-by: Marcel Schwittlick <marzzzel@gmail.com>