Bug 31465: (follow-up) Link to preference tabs directly

Bug 31465: (follow-up) Link to preference tabs directly

This patch enhances the mapping system for the help button to allow for
each tab of preferences to link directly to the relevent section of the
manual.

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
(cherry picked from commit 6d82b66a277caa879a5a7b0c8f05a84f795beb4d)

Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
(cherry picked from commit 78a2c2220689fde6ed1c2c88043889064aa76e4e)
Signed-off-by: Arthur Suzuki <arthur.suzuki@biblibre.com>