DevColors: Converts color values between RGB and hexadecimal

This class can be used to convert color values between RGB and hexadecimal representation.

It can take an array with the values of a color as separate RGB component values and convert the color to the hexadecimal representation used in the Web pages.

It can also do the opposite, i.e. converting the hexadecimal color values to the RGB representation.

The class can also validate color values in either the RGB or hexadecimal formats and determine whether the values correspond to a valid color.