Bug 20828: Step 4 of moremember is used for Housebound and additional attributes

Bug 20828: Step 4 of moremember is used for Housebound and additional attributes

This patch modifies the patron edit process so that "Housebound roles"
can be edited as a separate step.

To test, apply the patch and open an existing patron's detail page
(moremember.tt). Test the "edit" links for 'Housebound roles' and
'Additional attributes and identifiers' and confirm that each opens its
own edit page, and saving changes works correctly.

Signed-off-by: Cab Vinton <bibliwho@gmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>