Update 3d printing guidelines.

[martukas]

What has to be done
3d printing guidelines are somewhat outdated. Could use improvement.

Subtasks:

• Siraya website now includes chitu config files, so we may not need as many bespoke ones in our repo
• Chitubox config files may also be moved to Google drive, as they are not strictly part of vent design
• Instructions should point contributors to google drive for sharing intermediate files, rather than encouraging them to commit to repo
• Could include list of tools and materials needed for SLA print processing - snips, blades, etc..

How do you know it has to be done
It's evident that the docs are outdated. I am trying to print again after a moderate break and am noticing these incongruencies.