The whole protocol name thing is pretty weird. The getprotobyname functions
seem to only specify one mapping for name <-> ids, so all families/types
must use the same values. Plus the values used for the protocols are
standardized by IANA, so are always the same.
So, we drop using names for protocols, intead introducing an enum with
a few commonly availible and used protocols.
Previously we saved the location in various places which is unnecessary
and sometimes even wrong. For instance, we saved the address we bound to
which may not have the final port set.
