This patch adds the missing discharge help file and updates the moremember file with
info on discharges.
To test:
* Visit a patron
* View and confirm help is right
* Visit the discharge page on the patron
* Confirm help file loads and is right
Signed-off-by: Mark Tompsett <mtompset@hotmail.com> Signed-off-by: Jonathan Druart <jonathan.druart@koha-community.org> Signed-off-by: Tomas Cohen Arazi <tomascohen@unc.edu.ar>