Clarifying the editorial guidance on the Add A Tool page of COPTR

[anjackson]

Based on yesterday's Collaboration Café discussion, I have a proposal to improve the Add A Tool page:

• Make it clearer that links to e.g. blogs about how you are using the tools are very much encourage.
• Clarify that factual notes about specific limitations or 'gotchas' are welcome, but should ideally specify the latest known affected version of the tool, and link out to e.g. a related GitHub issue. If the issue has not been reported publicly, please sign the statement (using ~~~~).
• Add a link to the cheat-sheet https://www.mediawiki.org/wiki/Cheatsheet (and possibly other places too!)

If no-one complains, I'll look into implementing this. If anyone has wording suggestions, that'd be appreciated!

[anjackson]

Aside: Based on that discussion, I also added the 'add a tool' link to the sidebar (by editing https://coptr.digipres.org/MediaWiki:Sidebar).