Github repo from URL

Turns 404 github URL requests to the new repo creation page.

Have you ever typed a github URL that you wanted to make such as `/USERNAME/awesome-repo` only to be greeted with the GitHub 404 page? You know what would be nicer that a 404 page? The github new repo page with the name section *already filled out*. That's what this extension does. Never again will you click the "new repo" button! Simply navigate to the URL a be done with it! A veritable improvement.