function min( x, y ) {
	return ( x > y ) ? y : x; // doesn't account for +-0
}
Returns the minimum value of `x` and `y`.

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

@example
var z = min( 10.0, 3.14 );
// returns 3.14