PHP 7.4 compatibility for User model

• Fixed curly braces in User model deprecated error for compatibility with PHP 7.4

Bootstrap4 Kartik widgets

• Fixed admin panel pages with Select2 Kartik widgets (enabled Bootstrap4 mode through Yii::$app params)

Bootstrap4

Yii doesn't have a good support of all modern frontend features, however it has bootstrap4 package.

This release has a great upgrade - total replacement of bootstrap3 to bootstrap4.

Admin panel also takes a new beta version of AdminLTE 3.0-beta which has much more modern look, than previous version.

Nice looking starter

Pretty stable version.

Fixes:

• Admin user creation (problems with password and roles)
• Installation process: automatically creates .env and .htaccess files from examples

Refactored:

• Removed base module containing console migration commands patches
• Moved migration templates to database/migrations/templates
• Removed params.php
• Set minimal Yii version to 2.0.22

Renamed env example files and add dotenv-sync package

• Renamed .env-example in .env.example.
• Renamed public/.htaccess into public/.htaccess.example
• Added dotenv-sync package to check diff and sync .env with .env.example files

Fix register page

Missed use statement for RegisterForm class.

Fix yii rbac/scan for Windows OS

For some reason rbac/scan on Windows OS generated fatal error inside modules/admin/controllers/SettingsController.
Changed class inheritance and this fixed the problem.

Update config files with ::class call, instead of string names

Merge pull request #34 from justcoded/develop

Replaced className with PHP ::class in configs; added yii shell

Fix 'yii serve' command

• Fix './yii serve' command.
• Updated configs to PHP 7 syntax (with ::class call, instead of hard-coded text value)

Users migration fix after refactoring

Fixed existed migration after refactoring Migration to base module