ByteAnd()

         Makes an And of two bytes bit to bit

    Syntax:

         ByteAnd ( cByte1, cByte2 ) -> cNuevoByte

         cByte1 y cByte2 : Bytes to do the And.

    Description:

         Makes an And Between the two especified bytes and returns the
         new byte with the result.

    Return:

         The result byte of the And or Nil if any of the two entry bytes
         are not of the type character.

    Example:

         ? ByteAnd ( "O", "A" )