Glass clamp for heated beds

The tolerances are a bit tight for some glass sizes and print settings on the original version, so I updated those with the version 2 files.

Bed clamps for 200x200mm to 230x200mm 4mm thick glass on 220x220mm 3.3mm thick heated beds. Print two each of A and B orientations to get pieces for four corners.

Screw guide for 230x200mm glass:

* 4x 15mm or longer M3 screws (16..18mm is optimal)
* 4x 10mm or longer M3 screws (6..8mm is optimal)

Screw guide for 220x200mm glass (print the 230x2