Support gitlens & git-graph

This adds support for gitlens & git-graph via the toolbar button. It should be possible to refactor this to support opening it directly from the gitlens view (not sure about git-graph as it's a webview).

• Yes, I'll add a section in the README soon.
• Hmm.. not sure what this "(deleted)" means. It should be the commit hash, when it works. I'll try to look it up in the gitlens repo. EDIT: it's here. I'll see what I can do. I don't know how to reproduce it yet (how to get this "deleted" case).
• That's true. Both gitlens & git-graph does not provide an API. We can contact them and ask for exposing an API. In the meanwhile, I can refactor it out, maybe to a dedicated "externalExtensionsIntegration.ts" and the parsing will include error handling which will tell the user to file an issue regarding it. It'll name the extension which changed its format, so it'll be easy to fix.
• If you think the refactoration I suggested above bullet is good, then I'll do it. It would also enable us to add a context menu entry for gitlens.

Thanks and Purim Same'ach 🤡

I think this PR is kind of ready. The remining problems are:

• The (deleted) reference. Do you know how does it happen? do the commit you referred had some weirdness?
• Some diff-editors, s.t. comparing different commits, doesn't make sense to have the button I've added, because it only make sense to have it when comparing something with the "working tree" version of the file.

To address the second bullet, I'm thinking listening to opening editors and adding a ContextKey in case the editor is comparing "working tree" file, so in case it compares 2 commits, then we won't show the button. But I'm thinking adding it as an another PR.

What do you think?

The only other thing left is to add a section in the README, I'll do it soon.

• I'll re-check the (deleted) thing.
• I wonder if we can detect non working tree comparison based on the paths of the files since neither of them has "real" path but a temp one or something.

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.