function fresnels( x ) {
	return addon( x );
}
Computes the Fresnel integral S(x).

@private
@param {number} x - input value
@returns {number} S(x)

@example
var v = fresnels( 0.0 );
// returns 0.0

@example
var v = fresnels( 1.0 );
// returns ~0.438

@example
var v = fresnels( Infinity );
// returns ~0.5

@example
var v = fresnels( -Infinity );
// returns ~-0.5

@example
var v = fresnels( NaN );
// returns NaN