docs: boolean wouldIBeCoordinator(Collection<Address> leaving_mbrs) {
          List<Address> mbrs=gms.computeNewMembership(gms.members.getMembers(), null, leaving_mbrs, suspected_mbrs);
          if(mbrs.isEmpty()) return false;
          Address new_coord=mbrs.get(0);
          return gms.local_addr.equals(new_coord);
      }