Omnifixo - Field Box slim version

This is the new field box that is shipped with OF-M4.4 but in a 3D printer friendly version. 

This version takes advantage of the included magnets to hold the base securely as a lid. The box also includes slots that could be used to secure dividers/inserts or to place the base vertically if you have jobs that needs some extra reach.

For early versions of the base there might unfortunately be a collision between the rubber feet's and the box when positioned in vertical positions. I changed the design of the rubber feet's slightly during 2023, old one have a rim new one is cylindrical.

 There are overhangs (at the magnets) that need support while printing.