edit: enable Sublime Text project view

[mistydemeo]

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Code very similar to this was removed in c6b6fc6 because we had, at the time, moved away from the model where the Homebrew prefix was the repository. Now that we've actually moved back to that model, we've re-inherited exactly the same problems that inspired the original code.

In place of the original code, which specified the list of files to open in cmd/edit, this PR adds a Sublime Text project file and opens that with brew edit instead. That limits the code changes significantly, with the majority of the diff being indent-related. I've left a comment at the top of the Sublime project file to indicate how it was authored.

A similar PR to this was previously open in #10710. This version addresses Mike's comments in the original version.

[BrewTestBot]

Review period will end on 2021-08-03 at 00:00:00 UTC.

[BrewTestBot]

Review period ended.

[MikeMcQuaid]

Thanks for addressing my comments!