Add support for publishing taxonomies to PURLs.

[hkir-dev]

Work breakdown (estimated workload: 7 man-days):

• How to manage github user token?
  • Ask during release via a popup? (estimated workload: 2 man-days)
  • Get as part of config and store in a vault? (estimated workload: 5 man-days)
• Trigger our own script during release (estimated workload: 1 man-days)
• Check if already have a config (estimated workload: 1 man-days)
• Github rest API client to make a PR. (estimated workload: 2 man-days)
• Notify user (estimated workload: 1 man-days)