specify mpi variants conda_build_config.yaml

[minrk]

needed for rerender to get the mpi variants. Maybe #14 had this file but forgot to commit it?

Otherwise, rerender fails with:

  File "~/conda/lib/python3.6/site-packages/conda_build/utils.py", line 1574, in <listcomp>
    matches = [regex.match(pkg) for pkg in reqs]
TypeError: expected string or bytes-like object

because {{ mpi }} is None.

[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]

I guess that with https://github.com/conda-forge/conda-forge-pinning-feedstock/pull/93 we don't need this, right?

PS: I think I got the matrix right in #14, if not we can merge this one and bump the build number.

[minrk]

I guess that with conda-forge/conda-forge-pinning-feedstock#93 we don't need this, right?

Once that's released, yes, I think this should become the default behavior for repos with {{ mpi }}

I think I got the matrix right in #14

Yes, the matrix is definitely right in the rendered output, but rerender fails because the source of the matrix isn't in this repo. Did you have this specified somewhere that didn't get committed? Rerendering after this PR doesn't change the result at all, but before this PR rerendering master would fail because mpi is None.

[ocefpaf]

Awesome. Thanks @minrk!