New Map won't be saved

[adfx]

Hey,

first of all big thanks for your great work. Helps a lot with that map rotating issue.
Right after creating/sniffing a new blank map I sent a save command. I saw the folder created but sadly didn't check the content. Later when a restore was needed I realized the created folder is empty. The reason was pretty simple. I had no user_map0 and PersistData_2.data file at that point. I needed to create a forbiddenzone which can be deleted later. That creates those two files. Without all 4 files maploader.js fails saving a map. Here's the output:
`
Received Save Request: Grundkarte_leer_test
Created directory: /mnt/data/maploader/maps/Grundkarte_leer_test/
fs.js:114
throw err;
^

Error: ENOENT: no such file or directory, copyfile '/mnt/data/rockrobo/user_map0' -> '/mnt/data/maploader/maps/Grundkarte_leer_test/user_map0'
at Object.copyFileSync (fs.js:1728:3)
at copyFiles (/mnt/data/maploader/maploader.js:41:6)
at MqttClient.client.on (/mnt/data/maploader/maploader.js:27:3)
at MqttClient.emit (events.js:198:13)
at MqttClient._handlePublish (/mnt/data/node/node-v10.16.3-linux-armv7l/lib/node_modules/mqtt/lib/client.js:1162:12)
at MqttClient._handlePacket (/mnt/data/node/node-v10.16.3-linux-armv7l/lib/node_modules/mqtt/lib/client.js:351:12)
at work (/mnt/data/node/node-v10.16.3-linux-armv7l/lib/node_modules/mqtt/lib/client.js:283:12)
at Writable.writable._write (/mnt/data/node/node-v10.16.3-linux-armv7l/lib/node_modules/mqtt/lib/client.js:294:5)
at doWrite (/mnt/data/node/node-v10.16.3-linux-armv7l/lib/node_modules/mqtt/node_modules/readable-stream/lib/_stream_writable.js:428:64)
at writeOrBuffer (/mnt/data/node/node-v10.16.3-linux-armv7l/lib/node_modules/mqtt/node_modules/readable-stream/lib/_stream_writable.js:417:5)
root@rockrobo:/mnt/data/maploader/maps# ll Grundkarte_leer_test/
total 8
drwxr-xr-x 2 root root 4096 Sep 22 13:29 ./
drwxr-xr-x 9 root root 4096 Sep 22 13:29 ../
root@rockrobo:/mnt/data/maploader/maps#
`

I suggest to mention that in README or possibly skipping files if they do not exist. Thanks and regards