Old Landscape/Groups: Move "Display Preferences" items over to Grid Home

[urcades]

All of the options below should eventually* (when Groups is updated for increased visual/structural parity with Gridscape) be relocated over as "Grid Home" sysprefs:

The effect we eventually want to support is increased customization existing at the "root" of the Gridscape experience:

* "Eventually" meaning when we get around to updating the Groups app

[jamesacklin]

Will be good to build this functionality into %garden and then backfill Groups to look at that preference object.