This plugin monitors a single Minecraft server connected to BungeeCord. If the server is inactive for 30 minutes, it sends a command to AWS to shut the server down. If the server is down, and a player tries to connect, it sends a command to AWS to spin the server back up.
Extensibility with any hosting provider is a planned feature™.
Source Code: https://github.com/Kyu/DormantServer
Demo: