Improvement: Allow Neodymium config to be overwritten by system properties and system environment variables

[wurzelkuchen]

Quick Description

We should add the possibility to change our configuration from the outside. For example in CI/CD environments it would help to use environment variables to actually change the configuration. For example setting the base URL for different environments, without the need to touch the repository

User Story

As a test engineer, I want to have the possibility to change all the config values, without doing a commit each time so that I can run different pipelines for different configurations more easily

Functional Requirements

• [x] Use the features of the owner framework to allow system properties and environment variables to override our config.
• [x] The content of the dev-neodymium.properties should still overwrite ~everything else~ everything except system properties and environment variables.

Documentation Requirements

• [x] Add a note to the wiki

Test Requirements

• [x] Add some unit tests

[wurzelkuchen]

Update note: due to specifics in the owner framework, we decided to not have the dev-neodymium.properties as the highest point in the overwriting hierarchy, but the system properties/environment variables.

[georgkunze]

Code is ready for Recheck. Documentation done.