FileUpload update existing archive with filter

Low priority. Several considerations.

1. Basic function is download archive, extract, add filtered file into it, zip up. Upload new archive to filter channel. Then delete old archive and update PVPLog.filtered_msg_id .
2. The real annoying caveat is sometimes file will exceed limit, in this case we will have to abort above flow and simply make new zip for this upload.
3. Possible race condition if multiple uploads from same user allowed one after other and making or editing same zip.