Add UI for adding services to Oncall/ Allow option for services to be owned by multiple teams.

As far as I've been able to find there is no way to input services into Oncall without going directly to the database and manually entering the information in.

It would be nice if there was a form input page for services that would allow the users to input a service, mark whether it is owned by multiple teams, list the teams who own the service, and possibly enter in a URL for the service and links to monitoring services already utilized for that service (I.E. Nagios, Orion, Kibana, Etc).

Start by tracing how services and team ownership are currently represented, including the database path mentioned in the issue and any existing Oncall management UI. Define the form requirements for service details, multiple owning teams, a service URL, and monitoring links. Done means users can add and edit these details without manually changing the database.

Written by the indexing model from the issue text.