Support to export code to GitHub

[joaomoreno]

There are a few scenarios:

• Single folder open, no repo. Show welcome view content and status bar item to export the currently open file to a GitHub repository
• Single folder open, repo, but no remotes. Show status bar item to export the currently open file to a GitHub repository.
• Multi folder open, some repos with no remotes. Show status bar item to export one of the currently opened folder repos to a GitHub repository.
• Multi folder open, no repos. Show status bar item to export one of the currently opened folder repos to a GitHub repository.

[joaomoreno]

A few considerations:

• In order to create a repo, the user must pick between public and private, and we must present this choice properly with a warning lest they end up accidentally publishing private data to the wild. The default should be private; luckily this is now for free for everyone. 💯
• Authentication is an issue when dealing with the git cli (git push). The auth token might be sufficient but it needs to be hooked up to the git cli. For now we prompt the user to choose between HTTPS and SSH and it's up to them to have auth properly configured in git cli. In the near future we can have a contribution mechanism in the git extension to have external authentication handlers and then have the GHPR extension be such a handler and use the token for auth in the git cli.
• We should probably add a default .gitignore file with well known patterns... we don't want people checking in node_modules and stuff.
• Should we add an extra step to allow to create a repo in a certain org?

[joaomoreno]

Update:

• Authentication is now automatically handled in the core: Git: Provide automatic HTTPS authentication with GitHub vscode#96241
• Still need to figure out a .gitignore strategy

[joaomoreno]

Verification:

This month we added support to export a a repository to GitHub from the status bar, where the Sync action would normally be. If a repository has no remotes (multi-root or otherwise), it should still show the publish status bar icon which drives the user to export the repository to GitHub.

Additionally, when in a multi-root workspace and there are no repos, the Publish to GitHub action in the SCM welcome view should prompt the user to pick which workspace root it should publish.