Keycloak

[cehbrecht]

This PR adds support for an external Keycloak authentication service using OAuth2 tokens. Currently the OAuth client credentials workflow is described and supported.

Changes:

• support for token validation with keycloak
• docs and the overview image are updated.
• added an example notebook with a keycloak demo.
• OWS client registration is using now basic authentication.

For testing you need a keycloak instance which you can setup locally with Ansible:
https://github.com/bird-house/ansible-keycloak-playbook

[cehbrecht]

The keycloak demo with also tested at CMCC with Ophidia by @minomicetto.

@minomicetto Please note that I have opened a new repo for the keycloak notebook (master branch):
https://github.com/bird-house/ansible-keycloak-playbook

[cehbrecht]

@plogerais @jasonb5 You are welcome to add comments if you like.

[tlvu]

I don't know the code much so I was just reading the docs. Looks fine to me except the one problem I encountered.

+1.

[cehbrecht]

@tlvu @fmigneault thanks for review.