Better installator

[butschster]

• [x] Better structure of folders and files
• [x] Group all generators, packages, resources into logical modules
• [x] Split installer and configurator onto local parts, which can be tested separately
• [x] Unit tests
• [x] Fix Twig template (use stempler as aa boilerplate)
• [x] Register interceptors in DomainBootloader
• [x] Add translator component question
• [x] Add links to docs in config files
• [x] Improve Readme generation
• [x] Updates RR composer package versions
• [x] Check package dependencies
• [x] Register scaffolder Bootloaders for packages that contain it
• [x] After app is installed in tests (run unit tests inside app)
• [ ] Fix dependent questions in tests: https://github.com/spiral/app/blob/feature/project-structure/installer/Tests/Feature/Application/WebTest.php#L79