Modify Simulator entry point to be flexible as test driver

[georgi-l95]

Problem

Currently starting Simulator is only possible using the main method and without easy way to modify configuration or behaviour on the fly. That will create issues and obstacles, if we want to use it as a test driver for our E2E tests.

Solution

We'd need to modify the Simulator entry point, so that not only can be started using the main method, but via object instantiation and calling start method. We'd also want to be able to change configuration and more.