Enable admins to upgrade their WriteFreely installation from the admin dashboard.
This is continued from the discussion in T555.
- Download the latest version from an authoritative source
- Extract and replace only application files (not *.ini or keys)
- Restart the server (built-in?)
There are cases where we won't want this enabled or might want different behavior, such as in #write.as_for_teams. So maybe this ability is tied to build flags (seems ideal) or application configuration.