ars_SetFilter(ctrl, name, filterHash)filterHash before calling this routine.
      name is the name of the filter.
      
filterHash is a partially assigned
      Filter Attributes hash. 
      
Example:
This example changes the name and execution order of an existing filter.
      ($f = ars_GetFilter($c, "TEST:Filter")) ||
	    die $ars_errstr;
      ars_SetFilter( $c, $f->{name}, {
        name  => $f->{name} . "(renamed)",
        order => $f->{order} + 100,
      } ) || die $ars_errstr;
      
This function was introduced in version 1.90 of ARSperl