RepeaterGroup.addColumnHeaderTemplate Method
        
 Adds a column header template to the group.
 
         
        Parameters
        
            - template
            
 
            - 
                
Type: Template
The template to add. 
            - collectionIndex
            
 
            - 
                
Type: Number (Integer)
The index in the columnHeaderTemplates array. 
            - insertIndex
            
 
            - 
                
Type: Number (Integer)
(optional) An index in the array at which to insert the template. If not specified, the template will be added to the end.
Optional: True