Consistently name all VS commands

[jcansdale]

This PR uses a tip shared by @madskristensen to ensure that all commands have a consistent name.
https://twitter.com/jcansdale/status/991013150932729856
https://twitter.com/mkristensen/status/991018416222818306

Ahh, there is a way and it is undocumented. Prefix the name in the .vsct file with a period. Eg: .TestDriven.NET.Foo

What this PR does

Previously our commands would appear on the shortcuts search dialog with inconsistent prefixes (some didn't even contain GitHub and were difficult to find).

• This PR gives them all a consistent prefix of GitHub.

• Specify a CanonicalName for all commands (this is used in the Command Window)

• Specify a LocCanonicalName for all commands (used in Customize > Keyboard... dialog)

• Our commands now appear as follows

GitHub.Back
GitHub.Forward
GitHub.Refresh
GitHub.PullRequests
GitHub.ViewOnGitHub
GitHub.Help
GitHub.ConnectToGitHub
GitHub.ShowGitHubPane
GitHub.ShowCurrentPullRequest
GitHub.OpenLink
GitHub.CopyLink
GitHub.OpenFileInSolution
GitHub.Blame
GitHub.CreateGist
GitHub.NextComment
GitHub.PreviousComment

Previously they appeared as in the screenshot above + the following:

EditorContextMenus.CodeWindow.OpenFileinSolution
Edit.NextComment
Edit.PreviousComment

Reviewers

This PR is deliberately being kept simple. Is there any reason not to do this? 😉

I hope having all of these commands consistently named will allow for faster and more stable automation testing. //paging @meaghanlewis

How to test

These commands names are surfaced in a few places

1. On the Command Window if you start typing GitHub.

2. Right-click on a toolbar, Customize..., Keyboard... and start typing GitHub in Show commands containing.

3. They can also be accessed programatically via automation.

        void ShowGitHubPane(DTE dte)
        {
            dte.ExecuteCommand("GitHub.ShowGitHubPane");
        }

Future PRs

There is a bunch of functionality that is not being exposed as VS commands (e.g. show PR list of sync submodules). We should fix this but in separate PRs.

Fixes #1630

[meaghanlewis]

Thanks for doing this @jcansdale. It will be great to have these extra commands! ✨

[grokys]

LGTM! I did notice that some commands don't seem to do anything when run from the command window, such as GitHub.Help, though I don't think that's an issue with this PR.

[grokys]

This will also help with #1637 right?