Currently, this form does not point to any existing (resp. working) methods for authentication. For this purpose I need to develop some functionality to add user and have some data for testing.
Initilized package for creating modules. This still needs more testing to see if this is the real and best solution. However, I was able to generate module, so it seems promissing.
Add phpmailer and model generator into composer.json file. On server side, packages will be installed using composer, so that's the reason, why they are not in tree.
Michal Kváček