github auth as a backup if not using google oauth.

In my particular case, I don't have a company google account to
do oauth, but we share a github org, so let's use that.
Additional documentation on readme for github authentication
shiiiiiiiiiiiiiit dat debug line :bomb:
since this file is loaded from config.ru, cant use fetch.
Merge branch 'master' into github-auth

Conflicts:
	Gemfile
	Gemfile.lock
Only deal with the authentication type listed on OAUTH_PROVIDER

By mounting GithubAuth to '/auth/github', we can take the same
approach that omniauth does by looking for /auth/PROVIDER. This
changes the previous commits by not hitting the GithubAuth at
every request. whoops!
formatting changes for config.ru as well as instructions for readme
email can never be nil. Also new omniauth grabs user info different
don't append if graph.options are undefined
only redirect to graph profile if we import a single graph, otherwise back to graph palette
disable server-side image caching
Merge pull request #62 from brntbeer/github-auth

Github auth
requiring pry in prod breaks shit
don't override globals during graph url construction
no longer used in controller
add option for SVG, refs #18
mention SESSION_SECRET and better instructions for registering your GitHub OAuth app
example for Apache config to support CORS
instructions for running the db migration on Heroku, refs #66
be explicit this is a service dep, not a software dep