add docker image

docker/README.md

@@ -0,0 +1,24 @@
+# Docker image
+
+## Build
+
+From the root of this repository run:
+
+```
+./docker/build.sh
+```
+
+image name will be `restic/restic:latest`
+
+## Run
+
+Set environment variable `RESTIC_REPOSITORY` and map volume to directories and
+files like:
+
+```
+docker run --rm -ti \
+    -v $HOME/.restic/passfile:/pass \
+    -v $HOME/importantdirectory:/data \
+    -e RESTIC_REPOSITORY=rest:https://user:pass@hostname/ \
+    restic/restic -p /pass backup /data
+```