add G00 to Z up for G-code

files.html

modules/path/formats/g-code

programs/index.js

programs/machines/G-code/mill 2.5D stl

programs/machines/G-code/mill 2.5D stl connect

programs/machines/G-code/mill 2D PCB png

programs/machines/G-code/mill 2D png

programs/machines/G-code/mill 2D svg