Move GitHub Services to webhooks using GitHub or OAuth apps

https://developer.github.com/changes/2018-04-25-github-services-deprecation/
https://developer.github.com/v3/guides/replacing-github-services/

Deprecation timeline

• May 31, 2018: Submit your intentions for migrating or replacing your GitHub Service.
• October 1, 2018: GitHub discontinues allowing users to install services. GitHub Services will be removed from the GitHub.com UI.
• January 31, 2019: GitHub stops delivering installed services' events on GitHub.com.

The Captain Hook must migrate

• the "Jenkins (GitHub plugin)": useful but not required, this service is superseded by Captain Hook itself; moreover this service never managed multiple masters
• Codeship ? https://github.com/nuxeo/nuxeo/settings/hooks/7471790