Implement a mechanism to read the environment info from the test container

[tomuben]

The test container stores information about the test environment in some files in the root directory.
The information in those files contains useful information for the tests, for example:

• database port
• bucketfs port

We should provide a mechanism to read those files and return the content.

Acceptance criteria

1. Create a Python class which reads the information from /environment_info.json and provide convenience functions to access:

• database port
• bucketfs port