Gnc-Prefs: remove toolbar_style preference

This option should be handled by the environment, not by GnuCash

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23246 57a11ea4-9604-0410-9ed3-97b8803252fd
Gnc-Prefs: migrate GtkRadiobutton widgets (and associated preferences)

All GtkRadiokButtons now use the new preferences backend
so drop the GtkRadiokButton-Gconf wiring as well.

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23247 57a11ea4-9604-0410-9ed3-97b8803252fd
Gnc-Prefs: migrate gnc-plugin gconf machinery

Instead of storing a gconf callback function that will
eventually by attached to the preference when the
plugin is added to a window, simply do this for each
plugin internally in its own add_to_window override
function.
This had already been done in earlier commits for most
plugins. This commit cleans it up for the remaining
plugins and the base plugin code.

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23248 57a11ea4-9604-0410-9ed3-97b8803252fd
Gnc-Prefs: migrate GncCurrencyEdit widgets (and associated preferences)

All GncCurrencyEdits now use the new preferences backend
so drop the GncCurrencyEdit-Gconf wiring as well.

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23249 57a11ea4-9604-0410-9ed3-97b8803252fd
Gnc-Prefs: migrate GncPeriodSelect widgets (and associated preferences)

All GncPeriodSelects now use the new preferences backend
so drop the GncPeriodSelect-Gconf wiring as well.

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23250 57a11ea4-9604-0410-9ed3-97b8803252fd
Gnc-Prefs: migrate GncDateEdit widgets (and associated preferences)

All GncDateEdits now use the new preferences backend
so drop the GncDateEdit-Gconf wiring as well.

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23251 57a11ea4-9604-0410-9ed3-97b8803252fd
Gnc-Prefs: cleanup some remaining bits from the preferences dialog

It is now fully converted to the new preferences system

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23252 57a11ea4-9604-0410-9ed3-97b8803252fd
Drop option to customize gconf_path via command line or environment variable

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23253 57a11ea4-9604-0410-9ed3-97b8803252fd