Relax EndPointAddress equality requirement

There are tests which check that the address of an EndPoint is equal (as a ByteString) to the EndPointAddress which appears in events like ConnectionOpened on a peer to which it connects. I propose removing this requirement. Really we just need to ensure that connecting to the EndPointAddress given in the peer's event queue will indeed connect to the EndPoint which opened the connection. == may be sufficient for that but it's not necessary.

Some motivation: https://github.com/haskell-distributed/network-transport-tcp/pull/54 in network-transport-tcp we don't want to use the EndPointAddress reported by the peer as an identifier for a connection to it, because the peer could lie about it and thereby deny service to whoever really does have the given address. So the OS-determined host/port should factor into the EndPointAddress chosen by the contacted peer, but that can't be done because the equality constraint forces us to use the peer's reported address exactly.

Start with the tests that require an EndPoint address to equal the EndPointAddress in ConnectionOpened events, then trace how an EndPointAddress from a peer's event queue is used for connection attempts. Done means a connection reaches the EndPoint that opened it without requiring ByteString equality with the peer-reported address.