Move around some specs.

There was a lot of testing going on in that one feature spec.
Move perspective configuration to a reasonable spot.

It was just jammed above the template it was controlling.  Fun for
debugging, no good for displaying.  Moved it above the grid, which is
going to result is some screwy UI where we don't want to let you see the
delete/configure controls for that particular assignment while you're
already configuring it.  Later.
Allow closing the perspectives palette.
Fix assignments acting flakey after create.

Well that was a really fun bug.  Since it's completely undocumented, you
have to guess, and it jukes you by working 95% of the way with one
naming convention and 100% the other way.  The assignment was getting
persisted properly, but wasn't picking up its new ID after the AJAX call
came back.  Wow.

The BEST PART about this is its now causing a warning to appear in tests
that never appears in development.  There's now a "The response from a
findMany must be an Array, not undefined" in the test output.  Except it
fucking works now and never worked before, so what exactly is that shit?
A mystery.