[hierarchy-table] New kind of elements for columns: HierarchyList
[hierarchy-table] New kind of elements for columns: HierarchyList

When using HierarchyList elements for hierarchy columns (first columns), they automatically create necessary entries for all elements of the list.

Example:

Element #1 has multiple categories
  Category: Activity/Drink, Context/With friends

Element #2 has multiple categories
  Category: Activity/Restaurant, Context/With friends

When computing the HierarchyTable with Category|Elements as columns and Catgeory as Hierarchy Column, it will generate:
Activity:
 - Drink:
 - - Element #1
 - Restaurant:
 - - Element #2
Context:
 - With friends:
 - - Element #1
 - - Element #2

dubzzz/js-tools,dubzzz/js-tools