Run the server.  Returns with system error code.

def run(self):
        """ Run the server.  Returns with system error code. """
        normalized = os.path.normpath(self.path) + ("/" if self.path.endswith("/") else "")
        if self.path != normalized:
            sys.stderr.write("Please use full path '%s'" % (normalized,))
            return -1

        self.butterStore = ButterStore.ButterStore(None, self.path, self.mode, dryrun=False)
        # self.butterStore.ignoreExtraVolumes = True

        self.toObj = _Arg2Obj(self.butterStore)
        self.toDict = _Obj2Dict()

        self.running = True

        with self.butterStore:
            with self:
                while self.running:
                    self._processCommand()

        return 0