Add NRCan Gridded support

[Zeitsperre]

Pull Request Checklist:

• This PR addresses an already opened issue (for bug fixes / features)
  • This PR fixes #xyz
• (If applicable) Documentation has been added / updated (for bug fixes / features).
• (If applicable) Tests have been added.
• CHANGES.rst has been updated (with summary of main changes).
  • Link to issue (:issue:number) and pull request (:pull:number) has been added.

What kind of change does this PR introduce?

• Adds a configuration file for treating the NRCan Gridded 10Km dataset

Does this PR introduce a breaking change?

No.

Other information:

FYI @juliettelavoie @vindelico

[juliettelavoie]

What do you think of calling it NRCANmet instead of NRCAN to fit with PCIC? more context: https://github.com/Ouranosinc/ouranos_data_catalog/pull/33)
@vindelico, in your exchanges with them, what do they call it ?

Also, it would be nice to add the version in the attrs.

[vindelico]

What do you think of calling it NRCANmet instead of NRCAN to fit with PCIC? more context: Ouranosinc/ouranos_data_catalog#33)

Je proposait camel case: NRCanMet

@vindelico, in your exchanges with them, what do they call it ?

I have no confirmed information about that but I think they speak of it in terms of ANUSPLIN.
If they transfer their production log files as promised we might know more.

[juliettelavoie]

I prefer NRCANmet (not camel case) as this is how it is written in a lot of places(https://www.nature.com/articles/sdata2018299, https://www.pacificclimate.org/data/daily-gridded-meteorological-datasets, https://scenarios-climatiques.canada.ca/?page=CanDCS6-notes, https://esd.copernicus.org/articles/11/301/2020/, https://www.mdpi.com/2073-4433/11/12/1363)