set up parallel builds on CircleCI

[MothOnMars]

As a search-gov developer,
I would like my tests to run in parallel on CircleCI
so that I get my test results faster.

The search-gov repo can support up to 8 parallel jobs. See https://circleci.com/docs/2.0/configuration-reference/#parallelism.

This story depends on #59.

[nickmarden]

@MothOnMars can this be done by an open-source contributor?

[MothOnMars]

@nickmarden , I believe so, because all the configuration changes would happen in .circleci/config.yml. The internal settings for the repo already allow up to 8x parallelism. Per the docs, "If your repository is public, your CircleCI project will also be publicly available."

https://circleci.com/docs/2.0/oss/

[nickmarden]

Great, thanks for doing the homework to answer that for me. I wonder if @HalahAb would be interested in looking at this one...

[MothOnMars]

Resolved by #71.