added wifi section,
removed warning for registration,
removed sql etc sections

- Jargon Busting, A Computational Approach, Intro to Working with Data
- Add link to Workshop Overview
- Introduction to Git

and and was in the "What to Contribute" section

Sorry for the tiny commits!

Updated for v2.22.0 of the git bash installer. I'm not totally sure that using the Windows certificate store is the best thing to do, but in theory it should give a better chance of being able to deal with corporate firewalls that have their own root CAs.

Duplicate IDs for the macOS / Linux tabs in the "Text Editor" section
prevented anything from showing up when you click on the "Linux" tab.

Fixes #585

SWC changes: wrote a bash script that is tested against git-bash and the linux subsystem for windows thingo (via someone else in slack) to pull a copy of sqlite from sqlite.org and add it to local bin and then add that local bin to bash path.

DC changes: there's a pull request asking for the sqlitebrowser, so I added a check if the workshop is dc, which just points them at the sqlite browser download page.