(only sysop)
Syntax: MK(BOARD) <mainboard> <subboard>

MKBOARD adds a new boardname. If you want to create a new subboard you have
to add as first parameter the existing mainboard.

Example:   MKBOARD software baycom
           -> creates a new board SOFTWARE/BAYCOM if SOFTWARE
              is existing

If you want to create a new mainboard, you have to add a "/". The space
between "/" and boardname in this case is redundant.

           -> creates a new board SOFTWARE

The lifetime of new board is same as INFOLIFE. If you want to change it, use
LIFETIME command. File "bulletin.bcm" is updated automatically.