leap.common.events.server.ensure_server() raises if address is already in use
In the past, the function @ensure_server
@ wouldn't fail if there was a server running already.
Right now in the bundle fails since we run the server in the "launcher.py":https://github.com/leapcode/bitmask_launcher/blob/develop/src/launcher.py#L120 because we need to handle updates in there, and after that, the @ensure_server@ is run in the backend which fails.
(from redmine: created on 2015-06-10, relates #7127 (closed), relates #7149 (closed))