Added Dockerfile to run the mailbox.

Dockerfile

+FROM eclipse-temurin:11 AS build
+WORKDIR /mailbox
+COPY . /mailbox
+RUN ./gradlew x86LinuxJar 
+
+
+FROM eclipse-temurin:11
+RUN mkdir -p /root/.local/share
+VOLUME /root
+WORKDIR /mailbox
+COPY --from=build /mailbox/mailbox-cli/build/libs/mailbox-cli-linux-x86_64.jar /mailbox/mailbox-cli-linux-x86_64.jar
+CMD [ "java", "-jar", "/mailbox/mailbox-cli-linux-x86_64.jar" ]

README.md

@@ -98,6 +98,15 @@ And also ARM64 with
 
     ./gradlew aarch64LinuxJar
 
+As well as a docker container can be built with
+
+    docker build -t briar/mailbox .
+
+And run with
+
+    docker volume create briar-mailbox-1
+    docker run --name briar-mailbox --volume briar-mailbox-1:/root briar/mailbox
+
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