function clearBit( value, i ) {
	value &= ~( 1 << i );
	return value;
}
Clears a bit.

@private
@param {integer32} value - integer value
@param {NonNegativeInteger} i - bit to clear
@returns {integer32} updated integer value

@example
var v = clearBit( 5, 2 );
// returns 1