write tests

[zy4]

as of now we do have 0% coverage :(

[zy4]

@markolozajic
maybe dockerizing mongodb could be a solution too:
https://github.com/whisklabs/docker-it-scala

[zy4]

Rethinking: most important tests are:

• frontend test with webdriver or minmal ones with jsdom
• running actual jobs (functional tests)