Function lxcrond::ticker::minute_sync

pub fn minute_sync() -> DateTime<Local>

delay processing of the current thread until we are pretty much on the minute change over. This means when the main thread loops its starts at a minute boundary e.g. 23:23:00 and not 23:23:01 Idea is that cron jobs set for 0 3 * * * start at 03:00:00 and not much later.

returns the time used to calculate sleep durations, this is important because time might changte between real "now" and when we next compare cron triggers.