Accumulations for non-mars sources

[frazane]

As stated in the documentation:

The accumulations source is currently using the mars source internally. This will be changed in the future.

I find this feature to be extremely valuable and it would be great to see it implemented for other sources as well. Opening this issue to gather interest, keep track of ongoing developments and hopefully start some work on it. If someone wants to take the lead on this, I'd be happy to help.

[mchantry]

Hi @frazane please have a look at #317 we'd be happy to get your thoughts.

[frazane]

Looks like what we're looking for! However, I could not test it successfully yet. I suppose it's still a work-in-progress?

[b8raoult]

@flyIchtus is working on a solution here: #326

[b8raoult]

Note that it is GRIB only. If we want NetCDF, there is more work.