feat: add ftp backup storage

docker/Dockerfile

@@ -25,11 +25,15 @@ ENV AWS_REGION="us-west-2"
 ENV AWS_DISABLE_SSL="false"
 ENV GPG_PASSPHRASE=""
 ENV SSH_USER=""
-ENV SSH_REMOTE_PATH=""
 ENV SSH_PASSWORD=""
 ENV SSH_HOST_NAME=""
 ENV SSH_IDENTIFY_FILE=""
-ENV SSH_PORT="22"
+ENV SSH_PORT=22
+ENV REMOTE_PATH=""
+ENV FTP_HOST_NAME=""
+ENV FTP_PORT=21
+ENV FTP_USER=""
+ENV FTP_PASSWORD=""
 ENV TARGET_DB_HOST=""
 ENV TARGET_DB_PORT=5432
 ENV TARGET_DB_NAME=""