function isComposite( x ) {
	return isInteger( x ) && ( x > 1 ) && x !== PINF && isPrime( x ) === false;
}
Returns a boolean indicating whether a number is a composite.

@param {number} x - value to test
@returns {boolean} boolean indicating whether a value is a composite number

@example
var bool = isComposite( 4.0 );
// returns true

@example
var bool = isComposite( 5.0 );
// returns false