Use internal duration types, store time in seconds and propogate as
uint32_t when it is necessary. Update tick values as well.
Instead of generic `toInt(), overload between `strtol` and `strtoll`.
Current implementation of `settimeofday` rejects `struct tz` pointer,
make sure it's nullptr.
Sync is a simple enough routine... But, expect an already synced system
before triggering the sntp restart.