Function            cls - clear screen

  Syntax              #include <video.h>
                      cls();

  Prototype in        video.h

  Remarks             clears screen by Borland's clrscr(). I hated their
                      name for it, so I #defined cls().

  Return value        nothing.

  See also            clear()

  Example             #include <video.h>

                      main()
                      {
                           cls()
                      }