hour_shift caused non-unique index

[hailiangliu89]

WARNING: Because the original data is provided every month, at the
month boundaries there is untidiness if you use a time shift. The
resulting xarray will have duplicates in the index for the parts
of the day in each month at the boundary. You will have to
re-average these based on the number of hours in each month for
the duplicated day.

Hi Jonas, do you have an example of how to deal with the duplicated days? If not, I can try and add a function for it.

[coroa]

@nworbmot heat demand always fell into Tom's domain, so no i don't have an example at hand.

I'd appreciate new ideas on helping the user deal with the monthly boundaries.

[FabianHofmann]

upcoming in #20 see #79