Move hierarchical functionality into The Sql and Sqlng share drivers.

Move hierarchical functionality into The Sql and Sqlng share drivers.

Ansel is refactored to use the Sql driver for now. More refactoring is needed
before it can be switched back and forth between any drivers. (Need to compose
Horde_Share_Object with Ansel_Gallery instead of Ansel_Gallery extending the
share object).

Squashed commit of the following:

commit ed76634819d4e6c1737366d5ffafbfcc0630d12c
Author: Michael J. Rubinsky <mrubinsk@horde.org>
Date:   Fri Jan 21 20:59:26 2011 -0500

    Need to check against share ids in Ansel, not share_names

commit eb742b3414c3f27978beaa3c933f65f0e243efb2
Author: Michael J. Rubinsky <mrubinsk@horde.org>
Date:   Fri Jan 21 20:38:09 2011 -0500

    Cleanup/small refactoring for merged hierarchical driver

commit b3e50233d7288f3007ddea45cb35e0724c664aed
Author: Michael J. Rubinsky <mrubinsk@horde.org>
Date:   Fri Jan 21 20:28:16 2011 -0500

    extend Horde_Share_Object_Sql for now.

    Need to refactor so Ansel_Gallery is composed with Horde_Share_Object instead
    of extending it.

commit bb79f1f43aa7374cee325a70fd6849f52086ec75
Author: Michael J. Rubinsky <mrubinsk@horde.org>
Date:   Fri Jan 21 20:23:56 2011 -0500

    Simplify

commit 76ae1f5d2bb28a9267e336d912f4bd2cc49a4894
Author: Michael J. Rubinsky <mrubinsk@horde.org>
Date:   Fri Jan 21 16:37:14 2011 -0500

    Merge hierarchical functionality into base sql and sqlng drivers.