BOM: Add ofnLineItemUpdAttr directive to watch for changes in line_item attributes
Display quantity in field for BOM
BOM: applying ofnLineItemUpdAttr directive to quantity field, tracks changes with update-pending class
BOM: 'update-pending' class removed when value is init value
BOM dataSubmitter service changes class of relevant element based on response
BOM: Add css to to allow visualisation of update status
BOM: can update quantities of line_items