Publish project to GitHub

[shana]

When a project is on a local git repository but has no remote set up, we need to have a Publish UI to allow publishing repositories to a GitHub server without having to leave Unity.

• Detect if user is authenticated to control presenting "Publish" button
• Detect whether repository has been published (does it have a remote?)
• Hide Push/Pull buttons and show a Publish button (history view? branches view? everywhere?)
• Have a publish window that gathers the basic information for publishing a repo
  • Owner (either org or user), Name, Description (optional)
  • Make the repo public or private?

Validations:

• Is the user logged in? If not, we'll need to fire up the authentication flow before being able to publish
• Repository name
  • Name duplication - we can check whether the wanted name already exists with octokit
  • Spaces should be turned into dashes
• Private repository
  • If the user can't create private repositories, we need to show a useful error message

Advanced:

• Add support for selecting a license

UI Questions:

• The header should reflect whether the repo is published or not. Should we show the url there if it is?