Tagathon: add categories, keywords and tags to content

[Teebusch]

study group posts (and reports?) could/should have tags / keywords for searchability etc. It is fairly easy to add those in the markdown headers. I've done it for the latest study group posts as a "proof of concept"

[arockenberger]

Perhaps a good enough occasion to meet again for a StudyGroup (offline/online) and tag the posts!?

[Teebusch]

Sounds like a good idea. It's easy to do over a cup of coffee. We just need to come up with some sensible tags and categories.

Here's how to do it:

• each activity has its own markdown file here: https://github.com/uio-carpentry/uio-carpentry.github.io/tree/master/content/study_group/activities
• You can also use the "edit this page" link at the bottom of each activity's page on the website.
• add 'tags' and 'categories' to the yaml header and enter all categories and tags that apply (see this for an example)