v2.5.2

Added Discord Role Connection
Hints
i) POST /discord/role-connection/enable must be called to enable this function. (And /.../disable may be called to disable it.)
ii) User may get connected by logging in / connecting Discord.
iii) Metadata will be automatically updated when a job is submited, distance is added, user logged in or user connected Discord.
iv) User may manually update metadata with PATCH /member/roles/rank.