ForgeAutoShutdown

Added a watchdog that can automatically shutdown (or "kill") a Forge server if:

• The main thread hangs on a tick for more than a configurable period of time (default: 40 seconds, to not conflict with Sampler's 30 second stall reports)
• TPS (ticks per second) stays below a threshold for more than a configurable period of time

By default the watchdog will attempt a "soft" kill, allowing the server to save all data. If a soft kill lasts more than 10 seconds or if configured, a "hard" kill will be attempted.

Use at own risk; this feature needs more testing and has the potential to corrupt worlds. Therefore, it is disabled by default.

Other changes

• Daily shutdown is now an optional feature
• /shutdown command now only registered if voting is enabled
• ShutdownTask's tick handler is now only registered when scheduled shutdown begins
• Additional config file commentary