Add major_radius bool to HexLocations and rename apothem parameter to radius

[jdegenstein]

This PR fixes #633 by adding a major_radius: bool to HexLocations that defaults to False (to preserve current behavior). This PR is technically breaking because the prior apothem parameter had to be named to a more generic radius which can be either a major radius or minor radius (aka apothem).

Here is an example of the new functionality:

hex = RegularPolygon(1, 6)
with BuildSketch() as s:
    with HexLocations(1, 3, 3, False) as hloc:
        add(hex)
    with Locations((6,0)):
        with HexLocations(1, 3, 3, True) as hloc2:
            add(hex)

[gumyr]

Looks good to me. Your use case for this was something I didn't envision but is perfectly valid. Two of the examples would be broken though.

[jdegenstein]

Fixed the two examples and merged.