Run a GitHub gist. For now, this looks for an .html file and executes it. In the future, it can hopefully build larger sites and render non-executable files appropriately.
- pull down JS/CSS files in repo
- if there is no HTML file, but there is a JS file, run it and show output.
- render markdown with marked
- render JSON
- otherwise just show the text (preformatted?)
- maybe add a feature to list all gists for a user and let them click one to open/exec it.
- options to open in new window or replace current, optionally keep run gist header bar