Return a dict representation of KnwKBRVAL.

def to_dict(self):
        """Return a dict representation of KnwKBRVAL."""
        # FIXME remove 'id' dependency from invenio modules
        return {'id': self.m_key + "_" + str(self.id_knwKB),
                'key': self.m_key,
                'value': self.m_value,
                'kbid': self.kb.id if self.kb else None,
                'kbname': self.kb.name if self.kb else None}