searchbuilder.defaultCondition = 'null' does not trigger search

edknittel

Link to test case: https://live.datatables.net/heniqedu/1/edit?html,js,output
1. Select 'Add Condition'
2. Data: Position
3. Condition should default to 'Empty'
4. Note that the table does not update despite 3 records not having a Position set
5. There is no external way to even trigger the DataTable redraw; one must manually change the Condition to something else such as 'Not Empty' and then change it back to 'Empty' which defeats the purpose.

Description of problem: It's possible to define a searchuilder.defaultCondition for a column such as '=', '<', '>', 'null', '!null', etc. When selecting a SearchBuilder condition that does not have an input field such as Empty (null) or Not Empty (!null), SearchBuilder does not trigger a rebuild. This is likely because while the default condition loads, there isn't an onChange event that is fired.

Desired outcome: When a searchuilder.defaultCondition is set for a column and that default condition does not have a value input, then DataTables should automatically perform a rebuild with all of the current conditions.