add dev container

Dockerfile

@@ -1 +1,12 @@
-FROM alpine
+FROM alpine AS common
+# Insert here instructions to build your container, both for dev and production
+
+# Example - install a web server
+RUN apk add nginx
+
+FROM common as dev
+# Insert here all the dev only tools you need such as debuggers
+RUN apk add git
+
+FROM common as prod
+# Insert here production only things such as keys or production settings