Back & Restore avd not working

Operating System:
Ubuntu 18.04

Docker Image:
butomo1989/docker-android-x86-7.1.1

Docker Version:
17.12.1-ce

Docker-compose version (Only if you use it):
1.22.0

Docker Command to start docker-android:
docker-compose up --build -d

## Expected Behavior
I installed an apk on a fresh avd.
I expected the former avd to be used (with the installed apk) once I restart docker compose with
``` docker-compose stop && echo 'y' | docker-compose rm && docker-compose up --build -d```

## Actual Behavior
The avd is initialized from **scratch** again and doesn't include the previously installed apk.

## docker compose file

```
# Note: It requires docker-compose 1.13.0
#
# Usage: docker-compose up -d
version: "2.2"

services:
# Docker-Android for Android application testing
nexus_7.1.1:
image: butomo1989/docker-android-x86-7.1.1
container_name: appium_emulator_1
privileged: true
# Increase scale number if needed
scale: 1
ports:
- 6080
# Change path of apk that you want to test. I use sample_apk that I provide in folder "example"
volumes:
- ./video-nexus_7.1.1:/tmp/video
- ./local_backup/.android:/root/.android
- ./local_backup/android_emulator:/root/android_emulator
environment:
- DEVICE=Nexus 5
- CONNECT_TO_GRID=true
- APPIUM=true
- SELENIUM_HOST=selenium_hub
- AUTO_RECORD=true
```

## Update:
it seems like the file `devices.xml` is not created under the `.android` directory which causes the ```is_initialized()``` function to return ```False```