code: function(color){
  		for( var i=0, l= this.colors.length; i<l; i++){
  			if( this.colors[i].equals( color ) ){
  				return true;
  			}
  		}
  		return false;
  	}
docs: Checks if the given color is part of the list. Check is done by value,
  not instance.
  @param color
  @return true, if the color is present.