semiRoundedCube openscad module

Openscad module that allows easy creation of semi-rounded cubes.
Essentially it works as normal cube operation but takes a radius parameter that chamfers 8 of the edges, thus also chamfering the top and not just the vertical ones.

This version was made upon request as a easy way to make objects that will merge multiple cubes. The bottom surface is not chamfered so will be a good mating surface.

Warning: Will be heavier to process than a edges-only type rounding.

Warning 2: Make sure you overlap your objects by making the z height a tad taller and offsetting the objects into eachother. If you don't you may end up with bad union-results containing internal walls...

Note: Turns out this method is faster than minkowski due to the lower computational power required.