Mandate date/time update on devices without GPS or RTC

[satkiwii]

I havent followed up to see if this was added as a bug or todo but this is the last bit I recall seeing about it.

RTC time can drift

I just implemented the 8.5MHz clock that @mc-hamster found. I ran a quick test last night and in 12 hrs (ish) the new clock only drifted 1 second. So still not as good as a true 32.768 xtal but far better than what it was. I’m leaving the bug open though, to apply GPS based time corrections. It is an easy change and will go in eventually.