Rewrite auth to support a auth chain pr URL hidden as RestClient extension

GitHub Auth rewritten to use OAuth Token instead of username/password as
a simple username/password auth no longer works if combined with 2 phase auth.

.github-auth content should now be a "Personal Access Token" generated from:
https://github.com/settings/applications
Drone 1.2.0.Beta1 blog post
Minor language fixes to Drone 1.2.0.Beta1 release notes
Release blog for Graphene 2.0.0.Alpha5
Language fixes to Graphene 2.0.0.Alpha5 Release notes
some clarifications to Graphene Alpha5 blog