Docker container version (#39)

* + Dockerfile and compose file
+ Scripts dir and startup script
+ Build image npm script

* * Moves env to file

* + Tags image with info from package.json
* Moves image creation to script
* Updates README

* Update README.md

Co-authored-by: Sebastien Castiel <sebastien@castiel.me>

---------

Co-authored-by: Maxime Jacob <mjacob-no-reply@proton.me>
Co-authored-by: Sebastien Castiel <sebastien@castiel.me>

scripts/build-image.sh

@@ -0,0 +1,8 @@
+#!/bin/bash
+
+SPLIIT_APP_NAME=$(node -p -e "require('./package.json').name")
+SPLIIT_VERSION=$(node -p -e "require('./package.json').version")
+
+docker buildx build --no-cache -t ${SPLIIT_APP_NAME}:${SPLIIT_VERSION} -t ${SPLIIT_APP_NAME}:latest .
+
+docker image prune -f