A few of Dean's changes to the top nav.

Also some monkeying with bits of stuff that don’t work.
Removed the "help" text area at the top of the edit-block screen.
Don't need to set the order twice - was causing problems.
If there's no blocks yet jump from story-edit to new-block.
Sorting out problem with dragging new blocks.
Hide the view story block on the story edit screen.
Only hide the buttons where there's currently no blocks.