Motivation:

The market-services api can handle varieties of http method request.
Integration tests are necessary to ensure that basic functionalities
of the controller are not broken when new functionalities are added.

Modification:

- adjust the market-services controller:
    - post method to return 201, location url in the header and a json
          body that contain the newly create user
    - put method to return 200 if the uuid already exist or 201 if it
          is a new uuid.
    - get method now includes some limiting value for the parameters.
    - delete method now comply with the standard by returning 204.
    - use CerebrumEntityUuidGenerator.isValid to check the validity of
        a uuid and if invalid, CerebrumInvalidUuidException is thrown.
- add various tests scenarios to cover all HTTP methods in the
    market-services controller.

Result:

New 37 tests were added which leads to improve test coverage for the
market-services API. A little adjustment were made to the controller
to fix some minor bugs and make it conform with the standard.

Target: master
Review-at: https://gitlab.hzdr.de/hifis-technical-platform/helmholtz-cerebrum/-/merge_requests/26