Rounded time increments [Issue #71]

[lucasmodrich]

A (rough) prototype for #71

[Ellpeck]

Hi! Thanks so much again for this impl, sorry that it took me so long to get around to reviewing it!

I'm still a little undecided about the "allow time intervals to be the same" setting - as I said in the issue you linked:

I think the start/end time overlap prevention doesn't need a setting at all. If the start time is always rounded down and the end time is always rounded up, there isn't any danger of the start and end time ending up being the same. I think that's the easiest & best solution. Your idea of how the overlap prevention would work also poses a flaw: if the tracking was started at 11:56 and ended at 11:59, the tracker suddenly claims you worked from 12:00 to 12:05, a time increment that didn't even overlap with your actual work time. I also don't like the idea of there being a valid plugin configuration where the start and end time do end up being the same automatically - from my perspective, that's undefined behavior and shouldn't be "encouraged" by the plugin.

What do you think about this?