Add a docker dev environment that starts a container without building the image

+ Add dev.sh script to start the dev environment
+ Add generated flags to the .gitignore file

scripts/docker-entrypoint.dev.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+
+if ! test -f INITIALIZED; then
+    touch INITIALIZED
+
+    cd /app
+
+    npm i -g ts-node nodemon
+    npm i
+    npx prisma db push
+fi
+
+nodemon /app/src/app.ts