rm unnecessary base class

Closes #159

See merge request !521

remove warning about missing QObject initialization

Closes #158

See merge request !520

various minor improvements

See merge request !519

refactor sample builder

See merge request !517

...instead use typed and structured access to domain and GUI elements

harmonize GUI object population methods; reduce SessionItem usage in favor of correctly typed pointers

formfactor/particle: slight simplifications

See merge request !516

CMake: define and use variables CLANG, GCC, LINUX

See merge request !515

CMake: minor improvements

See merge request !514

Refactor sample model

See merge request !513