'Unlink (disassociate) the specified properties object.
@param others: The list object to unlink.  Unspecified means unlink all.
@type others: [L{Properties},..]
@return: self
@rtype: L{Properties}'

def unlink(self, *others):

    if (not len(others)):
        others = self.links[:]
    for p in self.links[:]:
        if (p in others):
            p.teardown()
    return self
