code: function( rule, priority, options ) {
  			this.rules.splice( this.findIndex( priority ), 0, {
  				value: rule,
  				priority: priority,
  				options: options
  			} );
  		}
docs: Adds specified rule to this group.
  
  @param {Function/Array} rule Function for function based rule or [ pattern, replacement ] array for
  rule applicable to names.
  @param {Number} priority
  @param options