Import oas include activedocs

[eguzki]

The OpenAPI Specification used to create the service is pushed as an ActiveDocs file, using the same system_name as the service.

This PR partially covers issue #90
Still missing: This OpenAPI Specification is patched to take into account the new environment:

• the host field is updated with the hostname component of the public production base URL
• the schemes field is updated with the scheme component of the public production base URL
• the basePath field is updated if rewriting rules have been set
• the securityDefinitions//authorizationUrl and securityDefinitions//tokenUrl fields are updated with the token and authorize endpoints listed in the OpenID Connect wellknown endpoint (when OIDC is in use)

The missing parts will be included in another PR

[mikz]

I'd seriously consider changing those unless + nil conditions into a more positive form and use variables.

[eguzki]

changed those unless + nil conditions