SSP-2007 Delay "main" admin UI store load until dependencies loaded

In the original SSP-2007 patch it was possible to render the admin
UI before all the dependent stores loaded, e.g. before the color
store had loaded in the elective admin UI. This actually mostly worked
OK, at least in that particular situation. The color column could
potentially just take a while to render.

I elected to reorder things a bit, though, to not trigger the
"main" store load until all the dependencies had loaded b/c we
don't really have a good way of indicating onscreen that a column is
still waiting for data. And I have no idea what chaos would ensue
if you tried to edit an incompletely rendered column.