When we present global views in RELAY, we mix local (UUID) and global (ProxyAddress) addresses. This works fine as both classes implement Address.
However, when we sort them, there's a ClassCastException, because UUID.compareTo(ProxyAddress) fails. ProxyAddress.compareTo(UUID) works.
ProxyAddressTest is the unit test for this.
SOLUTION: add code in UUID.compare() that compares to a ProxyAddress