restore toggle function and add test
mapdata checkboxes should use features.enabled()
When showing mapdata, background, or help panel, hide others
Deselect features that are hidden..
design enhancements..
* replace full width bottom bar with subtle list item
* move hidden feature details to list item tooltip
* simplify some of the text labels on the Map Data panel
* progressively hide some footer elements with media queries
2 things related to gatherStats auto-hiding..
* skip gatherStats on differenced redraws..
* force full redraw when gatherStats autohides/unhides features
  (before: extent redraws would happen, counts would update,
   but buildings/points would stay on the screen)
Add a filter fir a feature that's referenced in the url, work in progress
Preserve the selected item in the viewport
Single feature editing without zoom level restriction
Missed to override minzoom if there's a feature selected
Accessor for minimum editable zoom. Do not render vertices with tag less than minzoom
Refactor focussed feature filtering, change modes when unfocussed, fix tests
Test for focussed feature filtering
update test to check only relevant conditions
Test for drawing vertices when map is not editable
Remove shared variables between tests and use 'interesting' node to test drawing
work in progress: simplify geometries using simplify-js
Simplify features before rendering when the map is not editable
Fix tests for iD.svg.Path
Add simplify-js asset to build process