Sugar extension. Added sugar for name_search

Overloaded __call__ method to perform name search.
Example:

    ```
        In [2]: session.sdb['sale.order'](500)
        Out[2]: RecordList(sale.order): length=5

        In [3]: for so in session.sdb['sale.order'](500):
           ...:     print so.id, so.name
           ...:
        5397 P-08-03500
        4398 P-06-02500
        3402 P-03-01500
        2399 P-11-00500
        1800 1500

        In [4]: for so in session.sdb['sale.order'](500):
            print so.id, so.name
        KeyboardInterrupt

        In [4]: session.sdb['sale.order'](3500)
        Out[4]: R(sale.order, 5397)[P-08-03500]

        In [5]: session.sdb['sale.order'](3500).name
        Out[5]: 'P-08-03500'
    ```