Cleanup published tarballs

[michael-dean-haynie]

Acceptance Criteria:

• published packages should not include tests
• to distinguish "test" code from "production" code, all production code should be moved under the /lib directory of its respective package

Implementation:

• we can use the npm files field to specify the /lib directory and the index.js file: https://docs.npmjs.com/cli/v8/configuring-npm/package-json#files

References:

• https://blog.npmjs.org/post/165769683050/publishing-what-you-mean-to-publish.html
• https://stackoverflow.com/questions/25124844/should-i-npmignore-my-tests

[roy-coder]

Moved to https://bitovi.atlassian.net/browse/HATCH-543.