Test each geo-ref as saga text is loaded.
Keep a dict in geo.byRef to look up features by ref.
Added a dangling geo-ref to njála.html to demonstrate.
Reduced logging to what I think an editor would want.
Improving popup handling:
* Added a description field to feature popup, populated directly from feature properties.description in geojson file.
* Made the lat-lonfield in popup smaller and fainter.
* Stopped binding a pre-generated popup to each feature, but instead update the model on mouse-click, then populate popup lazily and show. This will be faster with a large number of features, and is cleaner MVC separation.
* Made #templates hidden. It was only by accident not clutering the page before.
* Improved logging slightly
* Improved logic which expands map to include newly selected point so it does nothing if the point is already in view. Previously, the map would some times keep zooming out pointlessly.
* Added lots of code documentation, in case future me or another developer has to work on the code.
Added bogus section markers to njála.html to trigger that functionality in the code.