zarr support

[ocefpaf]

According to the docs the defaults are:

The necessary CMake flags are as follows (with defaults)

-DENABLE_NCZARR=on – equivalent to the Automake –enable-nczarr option.
-DENABLE_NCZARR_S3=off – equivalent to the Automake –enable-nczarr-s3 option.
-DENABLE_NCZARR_S3_TESTS=off – equivalent to the Automake –enable-nczarr-s3-tests option.

I added those anyway to see if we can enable the feature. I'll turn the test on in the next commits.

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[ocefpaf]

Looking at the logs it is enabled! I'll activate the tests later.

[ocefpaf]

@rsignell-usgs and @kmuehlbauer, as I suspected the zarr support is enabled by default and it is working. See https://nbviewer.jupyter.org/urls/gist.githubusercontent.com/ocefpaf/5482c2a43fcdb811ea23dcb466a76420/raw/2afb9a1f6fc6a26e0894ce23f3c278f78772dec9/netcdf-c-zarr.ipynb

The zip files were not working though, we need to add libzip. Let's wait for conda-forge/conda-forge-pinning-feedstock#1418 to merge this one and get zip support. (In my gist above I have zip support b/c I used a local package built with it.)

[ocefpaf]

@isuruf I'm testing you suggestion but everything seems to be broken now. But I think it is unrelated :-/

[ocefpaf]

Do we need the quotes round the test name? It is still trying to run it :-/

[ocefpaf]

@dopplershift do you mind taking a look before we merge? If skipping that test is OK I'll trigger a pin update and a migration.

[ocefpaf]

@dopplershift and @kmuehlbauer note that this PR does not add the S3 features. We need to package https://github.com/aws/aws-sdk-cpp/tree/master/aws-cpp-sdk-s3 first to enable that.

[dopplershift]

@ocefpaf I'd like to see what #119 shows first.