code: function(first, second) {
  			if (_equal(first, second)) {
  				return true;
  			}
  			for (var i = 1; i <= first.length; i++) {
  				if (_equal(first, _rotated(second, i))) {
  					return true;
  				}
  			}
  			return false;
  		}
docs: loops are "equal" if their elements are equal when "shifted" to the right by some amount