Bug 13143: Followup - Correct the pause message

 Bug 13143: Followup - Correct the pause message

'read anykey' actually requires enter under sh.
This patch changes the string from:
    'Press any key to clear the screen...'
to
    'Press enter to clear the screen...'

TEST PLAN
---------
1) Apply the first two patches
2) Trigger the script.
2) Press 'q' or anything other than enter when prompted.
   --- You could type a whole sentence! Oops!
3) Press enter.
4) Apply this patch
5) Trigger the script.
6) Be happy that you aren't told any key will work.
7) run koha qa tools

Signed-off-by: Mirko Tietgen <mirko@abunchofthings.net>
http://bugs.koha-community.org/show_bug.cgi?id=13141

Signed-off-by: Mark Tompsett <mtompset@hotmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Brendan A Gallagher <brendan@bywatersolutions.com>