Pinch block y-bar clamp 2.0

This is a parametric one-piece y-bar clamp. It replaces two y-bar clamp pieces from Mendel or Mini Mendel, and requires no screws! The previous version ran the risk of delaminating under stress. This version is modified to print on its side, as per Erik's suggestion, which should make it stronger. The STLs also have 6.5mm and 8.5mm holes now, which should fit the M6 and M8 rods better when printed.

Update: on the third try (I need a heated bed), I got this to print without coming loose. The s