[FEATURE] Primitive: Box

[orgarten]

Is your feature request related to a problem? Please describe.
New primitive: Box of arbitrary size -> can be constructed by 6 planes, but would be beneficial to have this kind of setup in order to speed up traversal. Furthermore, setting up a box via planes is cumbersome if done every time a box is needed.

Describe a possible solution.

• Create 6 planes which construct the box
• call intersect for such a contsruct

Describe alternatives you've considered
Setting up 6 individual planes, which is error prone.

**Needed: **

• box blazeRT primitive

• box as embree primitive

• testing for blazeRT box

• testing for embree box

• support in blazertscene

• support in EmbreeScene

• testing of scene functions

[orgarten]

For implementing new geometries look at examples/geometry_template or the already existing geometries.

[tobiask-hfs]

I've started working on this task.