Fix mqtt userdb file (#13)

* Update run.sh

* Update config.json

mosquitto/config.json

@@ -1,6 +1,6 @@
 {
   "name": "Mosquitto broker",
-  "version": "0.1",
+  "version": "0.2",
   "slug": "mosquitto",
   "description": "An Open Source MQTT broker",
   "startup": "before",

mosquitto/run.sh

@@ -41,6 +41,7 @@ fi
 if [ "$LOGINS" -gt "0" ]; then
     sed -i "s/#password_file/password_file/g" /etc/mosquitto.conf
     rm -f /data/users.db || true
+    touch /data/users.db
 
     for (( i=0; i < "$LOGINS"; i++ )); do
         USERNAME=$(jq --raw-output ".logins[$i].username" $CONFIG_PATH)