Server in-game metrics/awareness: Statistics and smart schedules

[patschi]

It would be great to have pelican aware about certain metrics of the gameserver, such as current logged-in users. The smart use-cases could be following:

1. Have metrics/statistics about the gameserver itself in the UI, such as online players at certain times (put into several graphs).
2. Based on above information, allow kicking/banning users straight from the WebUI.
3. Allow the schedule to make more clever decisions, such as restarting server only when all players left the server. Let's say, schedule restart daily at 03:00. Then it is starting at this specific time and if needed, waiting until all players left the server.
4. Allow to perform certain macros/longer commands on the gameserver with a single click. (e.g. changing difficulty using multiple settings via rcon or similar)