'Cancels the hunt (removes Foreman rules, resets expiry time to 0).'

def Stop(self, reason=None):

    self._RemoveForemanRule()
    self.hunt_obj.Set(self.hunt_obj.Schema.STATE('STOPPED'))
    self.hunt_obj.Flush()
    self._CreateAuditEvent('HUNT_STOPPED')
    if reason:
        with aff4.FACTORY.Create(aff4.ROOT_URN.Add('users').Add(self.context.creator), aff4_type=aff4_users.GRRUser, mode='rw', token=self.token) as user:
            user.Notify('ViewObject', self.hunt_obj.urn, reason, self.hunt_obj.urn)
