Better template doc

[juliettelavoie]

Pull Request Checklist:

• [x] This PR addresses an already opened issue (for bug fixes / features)
  • This PR fixes #232
• [ ] (If applicable) Documentation has been added / updated (for bug fixes / features).
• [ ] (If applicable) Tests have been added.
• [x] This PR does not seem to break the templates.
• [x] HISTORY.rst has been updated (with summary of main changes).
  • [x] Link to issue (:issue:number) and pull request (:pull:number) has been added.

What kind of change does this PR introduce?

• improve template doc

Does this PR introduce a breaking change?

Other information:

Let's do it here instead of #233

[RondeauG]

I see a few things that could be adjusted too. I'll do it directly in the branch.