code: public static final String rgbToBrowserHexColor(final int r, final int g, final int b)
      {
          return "#" + toBrowserHexValue(r) + toBrowserHexValue(g) + toBrowserHexValue(b);
      }
docs: Converts RGB to hex browser-compliance color, e.g. "#1234EF"
  
  @param r int between 0 and 255
  @param g int between 0 and 255
  @param b int between 0 and 255
  @return String