* Change Dex port in local-environment from 4190 to 5556
Port 4190 is blocked by standards-compliant browsers (e.g. Firefox), as per https://fetch.spec.whatwg.org/#port-blocking.
Port 5556 is used by Dex in its example config files: 745e1114f3/examples/config-dev.yaml (L50)
* Fix upstream in local-environment/oauth2-proxy.cfg
http://httpbin.localtest.me:8080 is only exposed to the host, not to httpbin Docker network.
Causes Bad Gateway before.
* Do not expose unauthenticated httpbin service in local-environment
This defeats the point of having oauth2-proxy.
It has already been misleading by causing the bug fixed in cafc6af48fc38f6fe4395fb0c7e2638bc84e6091.
It serves as a bad example: users might accidentally expose the service they're trying to protect in the first place.
* Remove unnecessary httpbin.localtest.me alias from local-environment
* Adding one more example - keycloak - alongside with dex IDP.
* don't expose keycloak and proxy ports to the host
* specify email-domain list option in documentation
* get rid of nginx and socat to simplify the example as per https://github.com/oauth2-proxy/oauth2-proxy/pull/604#issuecomment-640054390
* get rid of the scripts - use static file for keycloak startup
* changelog entry
* Update CHANGELOG.md
Co-authored-by: Joel Speed <Joel.speed@hotmail.co.uk>
