[TimeLib] Missing Features/Suggestions

[zocka]

I think there should be a possibility to FormatDelta (Integer _Delta, EDurationFormats _Format) based on a delta from GetDelta (Text _Timestamp1, Text _Timestamp2) (I imagine internlly the current FormatDelta function first calculates a numerical delta anyway).

Use-case: store a delta (e.g. as game-duration) and compare new deltas against that numerical value, then output it.
(currently we would have to store an additional formatted string while comparing the numerical deltas and printing the formatted variables)