Feature Proposal: adjust clock time to refresh interval

Hi,

as i3status, if used with a `tztime` shows that module's clocktime on each refresh, the clock naturally lags behind realtime. If you for example use an interval of 60s, your clock if showing minutes can be up to 59s off.

To resolve this, one could introduce an optional setting to the tzdata module, either a correction value for the time directly or a boolean, leading to the time being corrected by the globally specified refresh interval.

If set, instead of lagging behind, the clock would run ahead of real time (and therefore never be late), which I personally find preferrable.

Would a PR implementing this have a chance of being merged?