Also allowed config-centralised default user settings for this change
and bought existing user-level view options into that default settings
system to be cleaner in code usage.
For #2081
Made so footer link ordering, names and urls can be set.
Cleaned up some of the setting-service and added support for array
setting types, which are cleaned on entry and stored as json with a new
type indicator column on the settings table for auto-decode.
Also added testing to cover this feature.
Related to #1973 and #854
- Was only used to disable registration when LDAP was enabled.
- Caused saved option not to show on settings page causing confusion.
- Extended setting logic where used to take ldap into account instead of
global override.
- Added warning on setting page to show registration enable setting is
not used while ldap is active.
For #1541
