feat: switch to 30 day month and 365 day year with leapless feature

[elrafoon]

Hello,

please consider merging this patch, that allows switching between 365.25/365 days per year and 30.44/30 days per month by enabling feature leapless.

I'm using humantime in project working with timeseries data, and the classic interpretation of 365d/y and 30d/m is required there.

I also think this can be a very common requirement in many other projects.

Thank you.

[djc]

I don't think Cargo features are a good fit for API like this, because it subtly but drastically changes behavior at a distance when a crate that enables this feature is pulled into your dependency graph.

It's also clearly not a common requirement, since this is the first time it has come up (as far as I know).

As such, I don't think it makes sense to merge this.

[elrafoon]

Ok, understand, I also thought about that dependency graph problem.

So would you accept a new patch that would extend struct Parser and struct FormattedDuration to include leapless: bool, defaulting to false, and doing the same thing as the feature did?

[djc]

Maybe, but it still feels like it would be pretty invasive relative to how niche your desired feature is.