Bug 19904: Release team for 18.05

Bug 19904: Release team for 18.05

First moved all relevant 17.11 release team entries to the development
section, and then updated the release team section from the wiki 18.05
roles page.

Test plan:
[1] Check if Koha team tab on about looks as it should.
[2] Verify changes with 17.11 and 18.05 roles.

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>