Reviewed adding IP recording to activity & audit log

Review of #2936

- Added testing to cover
- Added APP_PROXIES to .env.example.complete with details.
- Renamed migration to better align the name and to set the migration
  date to fit with production deploy order.
- Removed index from IP column in migration since an index does not yet
  provide any value.
- Updated table header text label.
- Prevented IP recording when in demo mode.

resources/lang/en/settings.php

@@ -117,9 +117,9 @@ return [
     'audit_deleted_item' => 'Deleted Item',
     'audit_deleted_item_name' => 'Name: :name',
     'audit_table_user' => 'User',
-    'audit_table_user_ip' => 'User IP',
     'audit_table_event' => 'Event',
     'audit_table_related' => 'Related Item or Detail',
+    'audit_table_ip' => 'IP Address',
     'audit_table_date' => 'Activity Date',
     'audit_date_from' => 'Date Range From',
     'audit_date_to' => 'Date Range To',