Added all docker stuff to the project

docker/docker-entrypoint.sh

@@ -0,0 +1,17 @@
+#!/usr/bin/env sh
+set -e
+
+cd /etc/shlink
+
+echo "Creating fresh database if needed..."
+php bin/cli db:create -n -q
+
+echo "Updating database..."
+php bin/cli db:migrate -n -q
+
+echo "Generating proxies..."
+php vendor/doctrine/orm/bin/doctrine.php orm:generate-proxies -n -q
+
+# When restarting the container, swoole might think it is already in execution
+# This forces the app to be started every second until the exit code is 0
+until php vendor/zendframework/zend-expressive-swoole/bin/zend-expressive-swoole start; do sleep 1 ; done