Major code refactoring

- updated dependencies
- renamed bin/server.php to bin/app.php
- changed namespace from API\* to Erpk\Harserver*
- dropped support for .phar archives
- added configuration wizard
- removed email and password options in standalone server
- unified request handling code and removed unnecessary duplication
- moved web/public/index.php to web/app.php
- added composer.lock to repository
- updated README.md according to new changes