function maxabs( x, y ) {
	x = abs( x );
	y = abs( y );
	return ( x < y ) ? y : x;
}
Returns the maximum value of `|x|` and `|y|`.

@private
@param {number} x - first number
@param {number} y - second number
@returns {number} maximum absolute value

@example
var z = maxabs( 5.0, -11.11 );
// returns 11.11