Rip out user, group and site design customization code

Rip out user, group and site design customization code

Squashed commit of the following:

commit 0bcfb6535115ec0a11669420f8689aeedc417bc8
Author: Zach Copley <zach@status.net>
Date:   Thu Jun 9 15:51:47 2011 -0400

    Remove design-related stuff from the API

commit 88da010256fbcaee1ff01d9507ea47d3225f2825
Author: Zach Copley <zach@status.net>
Date:   Thu Jun 9 15:40:16 2011 -0400

    Mop up misc design related code

commit 11958b064745b797b4c9f9f4b7e8f65e4c82ce83
Author: Zach Copley <zach@status.net>
Date:   Thu Jun 9 15:21:00 2011 -0400

    Remove Design DB_DataObject class and references to it in schema

commit f8540594728ce6ba4697eb21657ccb897a9fc127
Author: Zach Copley <zach@status.net>
Date:   Thu Jun 9 13:15:54 2011 -0400

    Remove design-related actions and widgets

commit ddf7b4d425b88b58956b8be06047d2a3e0560bd2
Author: Zach Copley <zach@status.net>
Date:   Thu Jun 9 13:10:57 2011 -0400

    Remove navigation / routing to design settings actions

commit e3f280f8780d99168edf37ef766956f281e9c5da
Author: Zach Copley <zach@status.net>
Date:   Thu Jun 9 13:03:09 2011 -0400

    CurrentUserDesignAction -> Action

commit 6780b1a07e1375a7fa0fd48c8bf3109d9a12e33e
Author: Zach Copley <zach@status.net>
Date:   Thu Jun 9 12:54:22 2011 -0400

    * GroupDesignAction -> GroupAction (new base class for group actions)

commit 2136377e895db274709a1d486f377f13946ccfd6
Author: Zach Copley <zach@status.net>
Date:   Thu Jun 9 12:36:40 2011 -0400

    OwnerDesignAction -> Action