Add the Three different height models of the CK PTS647.

See https://www.ckswitches.com/media/2567/pts647.pdf

NOTE. The only difference in the 3 footprints is the 3D Model. Each Size also has 3 difference difference Operating forces represented as x (N, M, K). Not included as no changes to the footprint or 3d model.

Please See 3d Model MR: kicad-packages3D!1006 (merged)

3D model Source: kicad-packages3D-source!405 (merged)