This allows to run integration tests during development and on CI
with the right dependencies. There are several changes that this
involves, but the gist of it is that a test environment is setup using
`docker-compose.test.yml`. This file is loaded by `resin-ci` during the
build, and ensures that integration tests are ran after setting up all
requirements. This commit also defines a test environment command that
can be setup using `npm run test:env` in order to run tests in a local
development machine.
