Replace ISO-8613-3 "true colors" with 256-color palette

[remkop]

Verify both modes on Cygwin, Babun and Linux

[remkop]

public class Colors {
    /** The Control Sequence Introducer (CSI) escape sequence {@value}. */
    static String CSI = "\u001B[";

    public static void main(String[] args) {
        for (int i = 0; i < 6; i++) {
            for (int j = 0; j < 6; j++) {
                for (int k = 0; k < 6; k++) {
                    int col = 16 + 36 * i + 6 * j + k;
                    System.out.print(CSI + 38 + ";5;" + col + "m" + col + " " + CSI + 0 + "m");
                }
                System.out.println();
            }
            System.out.println();
        }
        for (int i = 0; i < 6; i++) {
            for (int j = 0; j < 6; j++) {
                for (int k = 0; k < 6; k++) {
                    int col = 16 + 36 * i + 6 * j + k;
                    System.out.print(CSI + 48 + ";5;" + col + "m" + col + " " + CSI + 0 + "m");
                }
                System.out.println();
            }
            System.out.println();
        }
    }
}