Display updates could not add new updates

Caused, for example, boxes on the backside to not display properly.
Fixed a bug removing widgets

Where backside container didn't remove it from the list of
backside_widgets.
Added update_display to element attribute
Backside dimensions no longer forgotten

Was used once but wasn't recorded properly.
Fixed another bug removing backside widgets
Fixed a typo
Made the queue 're-entrant'

When running the old queue is processed while the new one may be built
up.
Stopped robots can be resumed

Previously sometimes they wouldn't resume because the flag that they
were animating was erroneously still set.
Fixed a bug copying erased widgets
Better handling of zero transforms

If all transforms are zero an exception is no longer generated.
Fixed recently introduced scheduling bug

Was losing some queue actions.

Added debugging info and commented out debugging print statements.
Shortened default backside

Was taller than page and scrolling was awkward.
Local storage keyed to href

Each URL has its own saved state.
IFrame test files

Works with FireFox to drag between frames but not Chrome. Though Chrome
allows drag into a frame from another window.
Top-level backside geometry restored

It isn't scaled like all other backsides
Unloading window causes backup

Localstorage updated when exiting.
Removed obsolete JSON

width and height of top-level backside since taken care of in its view
JSON.
Changed default top-level background colour

Full yellow was too intense.
Scale of backsides on backsides preserved

No longer become full size
Position of backsides on backsides preserved