Added NPCVendingMachine.UseRealTime toggle, will use the system clock instead of the in-game clock when adjusting prices
Recommend adjusting IntervalHours down dramatically when using this option so that prices don't take 5 real time days to adjust (setting this to 5 would match the current behaviour)
If changed at runtime resetDynamicPricing should be called afterwards to resync the pricing to the new clock
This would also have a side effect of making prices adjust while the server is offline - prices will be processed to make up for the missing time when a server is booted up again