If the endpoint is unable to send information to the service control backend, it shouldn't crash the endpoint. Fixes #269
Adding the readonly back for the serviceControlBackendAddress! Relates to #269
When the endpoint containing the SC plugins start and if the SC queue is not found, then we fail fast. Also if the endpoint is repeatedly failing when trying to send messages to SC, then we also trigger the circuit breaker and fail fast.

Relates to #269
Catching just QueueNotFoundException on startup will still fail the endpoint if another exception comes through but without the nicer error message, so it makes sense to just catch Exception instead. Relates to #269
Merge pull request #275 from Particular/issue-269

If the endpoint is unable to send information to the service control, it should fail fast