Add Binary Partition structure

Octree structure where you can insert, remove and check collision between meshes.

E.g.: Moving Sphere/Capsule:
`bsp.check(Vector3 oldPosition, Vector3 newPosition, radius);`

Dynamic size is a must. If a triangle point or a particule is outside the root node (AABB) we need a bigger node. Recreate the tree.

Code can be found at [propan-storage](https://github.com/Harium/propan-storage/compare/add-triangle)

- [x] Insert Vector3
- [x] Find Vector3
- [x] Add a dynamic size tree
- [x] Use gdx [Bounding Box](https://github.com/libgdx/libgdx/blob/master/gdx/src/com/badlogic/gdx/math/collision/BoundingBox.java)
BB.intersect(bb) could be slower (don't use it).
- [x] Create a triangle class
- [ ] Add Triangle to libgdx
- [x] [Calculate normal](https://www.khronos.org/opengl/wiki/Calculating_a_Surface_Normal) in constructor
- [x] Port the intersection algorithm
- [ ] Update [Intersector](https://github.com/libgdx/libgdx/blob/master/gdx/src/com/badlogic/gdx/math/Intersector.java)?
- [ ] Test it