Lightweight end effector plate for Delta

Parametric, lightweight plate for an end effector for Delta-style printers. Accepts groove mount with a novel snap-in mechanism. Accepts magnets (ball-on-rod designs).

Built for Eric Sammut's Prometheus hotend, but should work for many others including E3D and aluhotend and really any hotend that mounts its fan directly to the heat sink. With minor modification, fan mounts could be added to this plate.

In the future, I want to build a version which raises the hotend to avoid losing build v