Categorize tutorials list

[mabelzhang]

🎉 New feature

Categorize tutorials so that it’s easier for users to find what they need. (Also fixed formatting inconsistencies as I clicked through all the tutorials.)

Previously, all the tutorials were in a big list of arbitrary order. As the number of tutorials grew, we continued to add to the list but did not index them in a digestible way.

This PR doesn’t aim for a perfect categorization. It’s just a “better” categorization than what it is now - any categorization is better than no categorization.

It can always be modified or refined again later.

Summary

I just went down the list and looked for what natural groupings there were. The way I structured the page is meant to go in a general progression from beginner, intermediate, advanced users, to developers. Aside from that, there were sets of tutorials for GUI, Blender, and very very specific tutorials for one system plugin that only some users would find useful, so I grouped them accordingly.

Open to feedback.

Test it

Preview the rendered Doxygen pages in build/gz-sim7/doxygen/html/tutorials.html

Checklist

• Signed all commits for DCO
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

[codecov]

Codecov Report

Merging #2028 (40ea620) into gz-sim7 (b2c576b) will decrease coverage by 0.03%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           gz-sim7    #2028      +/-   ##
===========================================
- Coverage    65.02%   65.00%   -0.03%     
===========================================
  Files          354      354              
  Lines        28636    28636              
===========================================
- Hits         18621    18615       -6     
- Misses       10015    10021       +6     

see 1 file with indirect coverage changes

[azeey]

This looks really great, thanks! I have just one minor comment about a heading.

I was also talking to Chris about this and he suggested the idea of documentation having four parts: concepts, tutorials, API, and how-to guides. I've also found https://documentation.divio.com/ and https://docs-guide.readthedocs.io/en/latest/doctypes/ that more or less align with those. Maybe we can start thinking about our documentation in these terms.

[mabelzhang]

Yeah, he told me about those 4 categories they incorporated for ROS 2 docs. We should brainstorm a bit about that...
Thanks for the links! I'll have a closer read. The video is already entertaining :D