gnucash maint: Multiple changes pushed

[Geert Janssens]

Updated	 via  https://github.com/Gnucash/gnucash/commit/d4e4062c (commit)
	 via  https://github.com/Gnucash/gnucash/commit/24fa2899 (commit)
	 via  https://github.com/Gnucash/gnucash/commit/26b2d7ca (commit)
	 via  https://github.com/Gnucash/gnucash/commit/c6103a5c (commit)
	from  https://github.com/Gnucash/gnucash/commit/16184daf (commit)



commit d4e4062c9310f50729c94b73e9f2bd80382fabfb
Author: Geert Janssens <geert at kobaltwit.be>
Date:   Sat Oct 16 10:48:55 2021 +0200

    Remove redundant function declaration
    
    gnc_load_scm_configuration is declared and defined in gnucash-core-app.

commit 24fa289952257cb8a2f2b9d59024be59d05888e3
Author: Geert Janssens <geert at kobaltwit.be>
Date:   Wed Oct 6 18:53:36 2021 +0200

    GSettings - rework internal helper functions to use more C++

commit 26b2d7ca7878776a7c6777cd30e1b19185b72983
Author: Geert Janssens <geert at kobaltwit.be>
Date:   Wed Oct 6 17:11:00 2021 +0200

    GSettings - make most of the api private
    
    All preference calls should happen via the gnc_prefs_... apis.
    The gnc_gsettings_... apis are an internal implementation of this.

commit c6103a5c171f459b6ca070c61bcde939885ae613
Author: Geert Janssens <geert at kobaltwit.be>
Date:   Wed Oct 6 16:50:57 2021 +0200

    Add structure to map migrated preferences to old ones
    
    This can be used to keep both in sync in the period between
    initial migration and eventual obsolence.
    Note only non-obsoleted, migrated preferences are tracked.
    We don't want to resync preferences that have been
    obsoleted (reset). That would nullify the whole idea
    of making them obsolete for future removal.
    
    This commit only adds the mapping, synching will follow in a future
    commit.



Summary of changes:
 gnucash/gnucash-commands.hpp           |   4 -
 libgnucash/app-utils/gnc-gsettings.cpp | 277 +++++++++++------
 libgnucash/app-utils/gnc-gsettings.h   | 550 ---------------------------------
 libgnucash/app-utils/gnc-prefs-utils.c |   1 +
 4 files changed, 189 insertions(+), 643 deletions(-)