Improve Docker Compose documentation and example (#95)

- Clean up the example `docker-compose.yml` file by removing unnecessary
configuration/comments and add missing volume declaration
- Update the project README.md with instructions on how to use the
project with Docker Compose

README.md

@@ -37,7 +37,13 @@ To initialize and add account to the bridge, run the following command.
 docker run --rm -it -v protonmail:/root shenxn/protonmail-bridge init
 ```
 
-Wait for the bridge to startup, use `login` command and follow the instructions to add your account into the bridge. Then use `info` to see the configuration information (username and password). After that, use `exit` to exit the bridge. You may need `CTRL+C` to exit the docker entirely.
+If you want to use Docker Compose instead, you can create a copy of the provided example [docker-compose.yml](docker-compose.yml) file, modify it to suit your needs, and then run the following command:
+
+```
+docker compose run protonmail-bridge init
+```
+
+Wait for the bridge to startup, then you will see a prompt appear for [Proton Mail Bridge interactive shell](https://proton.me/support/bridge-cli-guide). Use the `login` command and follow the instructions to add your account into the bridge. Then use `info` to see the configuration information (username and password). After that, use `exit` to exit the bridge. You may need `CTRL+C` to exit the docker entirely.
 
 ## Run
 
@@ -47,6 +53,12 @@ To run the container, use the following command.
 docker run -d --name=protonmail-bridge -v protonmail:/root -p 1025:25/tcp -p 1143:143/tcp --restart=unless-stopped shenxn/protonmail-bridge
 ```
 
+Or, if using Docker Compose, use the following command.
+
+```
+docker compose up -d
+```
+
 ## Kubernetes
 
 If you want to run this image in a Kubernetes environment. You can use the [Helm](https://helm.sh/) chart (https://github.com/k8s-at-home/charts/tree/master/charts/stable/protonmail-bridge) created by [@Eagleman7](https://github.com/Eagleman7). More details can be found in [#23](https://github.com/shenxn/protonmail-bridge-docker/issues/23).

docker-compose.yml

@@ -3,16 +3,12 @@ version: '2.1'
 services:
   protonmail-bridge:
     image: shenxn/protonmail-bridge
-    # build:
-    #  context: ./build
-    #  dockerfile: Dockerfile
-    container_name: pm_bridge
     ports:
       - 1025:25/tcp
       - 1143:143/tcp
     restart: unless-stopped
-    stdin_open: true 
-    tty: true
+    volumes:
+      - protonmail:/root
 volumes:
   protonmail:
     name: protonmail