📝 add Docker section to the readme

Author: techouse

README.md

@@ -76,4 +76,26 @@ Options:
   --debug                         Debug mode. Will throw exceptions.
   --version                       Show the version and exit.
   --help                          Show this message and exit.
-```
+```
+
+#### Docker image usage
+
+If you don't want to install the tool on your system, you can use the Docker image instead.
+
+```bash
+docker run -it \
+    --workdir $(pwd) \
+    --volume $(pwd):$(pwd) \
+    --rm ghcr.io/techouse/sqlite3-to-mysql:latest \
+    --sqlite-file baz.db \
+    --mysql-user foo \
+    --mysql-password bar \
+    --mysql-database baz \
+    --mysql-host host.docker.internal
+```
+
+This will mount your host current working directory (pwd) inside the Docker container as the current working directory.
+Any files Docker would write to the current working directory are written to the host directory where you did docker
+run. Note that you have to also use a
+[special hostname](https://docs.docker.com/desktop/networking/#use-cases-and-workarounds-for-all-platforms) `host.docker.internal`
+to access your host machine from inside the Docker container.