Function:     Att()
Purpose :     Change attribute of area of the screen
Usage   :     Att(<expN1>, <expN2>, <expN3>, <expN4>, <expN5>, [expC] )
Params  :     expN1 - top row
              expN2 - left col
              expN3 - bottom row
              expN4 - right column
              expN5 - attribute to set area
              expC  - character to fill area with
Returns :     nothing.
Found in:     att.c