Create octokit client
Change repository API to use octokit
Change fork API to use octokit
Fix return result
Change pull request API to use octokit
Fix wrong reference to octokit
Return octokit.PullRequest
Use octokit for authorizations API
Use octokit for Statuses API
Use octokit for issues API
Use octokit for Releases API
Fix octokit import path
Merge branch 'integrate_with_octokit'
Fix some errors from octokit integration.

It seems there were a few places where the return statements were forgotten.
Not sure if this was intentional or just missed? Some of the tests were
throwing errors while I was trying to squash problems.