Implementation of a subsystem for authentication, authorization and role-based access control.

Development version which contains the implementation of many more entities that are required for the creation of a full-fledged club management software. The application was also updated to now use the recently released non-dev Phoenix 1.7 version.

First basic (development) version that has a minimal, working set of features (Authentication, Clubs, Departments), a clean UI which serves as foundation for further developments, zero failing test cases and no linter warnings.