Guided rule editor: When the operator is "in" or "not in" values should be created with list widget rather than separating with commas

When the operator is "in" or "not in" the list of values (for types other than enums) are defined by typing literal values separated by commas into a TextBox. This should be changed to use a new widget that allows a list of values to be created, with the value editor being correct for the field's data-type. This widget will also need to be used in the Template Data grid when the list is defined as a template key.