Initial project-setup.
Initial setup of domain-module.

Added participant entity and its unit-test.
Created module for persistence-api.

Created interface for participant-repository.
Created mybatis-specific implementation of persistence-api.

Created PersistenceMapper and Repository-Implementation including depdencies and Unit-Tests.
Created integration-test module for mybatis-based persistence module.

Implemented integration-tests for MyBatis implementation of ParticipantRepository.
Created module for JavaFX-UI

Added initial version of Participants-View