Health endpoint and more detailed metrics

Merge pull request #243 from abakusbackup/update-tracks

Add more information to the product sale track call

Allow null username

1.1.0

Merge pull request #220 from abakusbackup/doppins/babel-eslint-equals…

Use npm in docker

• Replace yarn with npm in docker, yarn fails.

Initial docker release with version

1.0.1

Release docker image on tag hook