Moogroo's VSA volume

Volume histogram:
// If Volume is less then the previous 20 intervals, Volume is gray.
// If Volume is greater then the previous 40 intervals, Volume is black.
// If Volume is less then the previous 2 intervals, Volume is purple.
// If Volume is less then the previous, Volume is red.
// If Volume is greater then the previous, Volume is blue.
// Other - white.
// You can add on the indicator a 2.5 Standart Deviation of a 20 period
// Bollinger Band Shifted 3 periods forward.