Werk #5192: Added new filter operators for list-valued columns

Previously only 4 operators were available for filtering list-valued columns:

• =: checks that the list is empty
• !=: checks that the list is non-empty
• <: checks that an element is not contained in the list using equality
• >=: checks that an element is contained in the list using equality

6 new operators have been added:

• <=: checks that an element is contained in the list using case-insensitive equality
• >: checks that an element is not contained in the list using case-insensitive equality
• ~: checks that an element is contained in the list using a substring regex match
• !~: checks that an element is not contained in the list using a substring regex match
• ~~: checks that an element is contained in the list using a case-insensitive substring regex match
• !~~: checks that an element is not contained in the list using a case-insensitive substring regex match

To the list of all Werks