Add ESModule Build - Closes #58

[petermikitsh]

Summary

(If you have not already please refer to the contributing guideline as described
here)

• Tell us about the problem your pull request is solving. See Ship a module build #58
• Are there any open issues that are related to this? See Ship a module build #58
• Is this PR dependent on PRs in other repos? No.

[petermikitsh]

The build failure is unrelated to this change set.

This package depends on feathers-tests-fake-app-users, which has an integration issue with sift.js.