Report layout breaks if custom filters are added without custom field selections

The report FieldSelection and Filters tpls are both determining whether to add various aspects of formatting according to whether the group_title is set for a given custom group.

This means that if you try to set filters without setting fields the layout breaks.

More appropriately the value assigned should tell the form which of the 2 to display and not treat the presence of the title as a magic clue.

NB - this will be a small fix