Handle other anomaly values in ring/route

[jamesnvc]

Currently only :incorrect and :unsupported anomalies are mapped to HTTP status codes.

The helper function should handle other anomaly values with different status codes.

    :unavailable   can-retry
    :interrupted
    :incorrect              400  (fix caller bug)
    :forbidden        403  (fix caller creds)
    :unsupported        405  (fix caller verb)
    :not-found        404  (fix caller noun)
    :conflict             (coordinate w callee)
    :fault            500  (fix target bug)
    :busy       can-retry   503  (back-off and retry)