The JSON format for each task is:
{ title : string
, children : [id,...]
}

Task 0 is the root task.  It does not appear, except that it's children form the list.
Additionally, the key "task-id" gets the current task id from localStorage

Things left todo:
 * drag/drop
   - fix issue with cursor not being what activates the drop zone
   - fix issue with editing being activated on mouseup
 * intercept and escape html in the task title
 * cleanup code
 * modernizer feature tests
 * theming
   - images for buttons
   - logo (http://www.fromoldbooks.org/)
   - typography (http://www.linuxlibertine.org/)
 * dates
 * cloud storage/syncing
   - localStorage event listener
   - write functions that encapsulate stores to localStorage
   - trigger refreshes?
 * make work offline with cache manifest