raft: overload operator<< for debugging
raft: overload operator<< for debugging

Overload operator<< for ostream and print relevant state for server, fsm, log,
and typed_uint64 types.

Signed-off-by: Alejo Sanchez <004be06a28e38b437b038f9b5c0b9f5758b792e9@scylladb.com>

scylladb/scylla,scylladb/scylla,scylladb/scylla,scylladb/scylla