Function:   MouseThere()

               MouseThere() reports whether a Mouse Driver is
               installed. If this functions succeeds by returning
               .t., then your clipper Application can make use of
               any of the MouseXXXXX() routines available in the
               Expand library, as a Mouse driver (MOUSE.COM) is installed.

               All Microsoft compatible mouses are supported, there now
               is also support for Three Button mouses. Although it seems
               that two buttons is more than enough in most cases.

               Note that calling this function also initialises
               the Mouse, this only occurs the first time the
               function is called, after that, MouseThere() will
               just return the result. So calling it the first
               time in your program might take some time
               (MicroSoft's Mouse takes nearly a second), but
               after that, it's immediate, this function is thus
               perfect to isolate specific parts of your Clipper
               applications that make use of the Mouse (see Usage).

               Note that you need to call MouseShow() specifically
               to make the mouse visible.

   Syntax:     MouseThere().

   Arguments:  None.

   Returns:    Logical, .t. if mouse is there, it is then
               initialised (only when called the first time),
               .f. otherwise (don't use any mouse
               calls in that case!)

   Usage:      if .not. MouseThere()
                    ? 'I want to run with a bloody Mouse!'
                    ? 'So go get one, install it, retry and'
                    ? 'then.. I just might run for you!'
                    Quit
               end

               Or:

               * - Here's how to isolate some code:
               * - Supposing you're using MouseEdit()..
               if MouseThere()
                  Msg('Use Mouse to move, [Left Button]-Invoke'+;
                      '[Right Button]-Quit')
               else
                  Msg('Use [Cursor] to move, [Enter]-Invoke, [Esc]-Quit')
               endif
               * - Now call the edit()...
               MouseEdit(.....blabla..)
               * - MouseEdit() does not require a Mouse, it just
               *   supports it!