Fix signature validation
Codeception test adjustments for basic and advanced applications

- Moved everything test-related into `tests` directory. Codeception tests are in `codeception`.
- Removed database module since we're using fixtures and migrations.
- Moved console entry points and bootstrap into `tests/codeception/bin`.
- Adjusted travis build scripts.
- Adjusted documentation to be consistent and reflect changes made.
Removed db module from basic app, renamed _helpers to _support and _logs to _output
Renamed guy classes to actors, fixed phpdoc and code style
Exposed basic app entry URL via codeception.yml, refactored configs of advanced app to read from config and define entry script in a single place
Adjusted test configs structure
Fixed copyright year in batch files
Prefixed constants to avoid possible naming conflicts
Renamed YII_ROOT_DIR → YII_APP_BASE_PATH
Adjusted testing namespaces in application templates
Added faker to basic app console commands, adjusted readme to mention database setup
Used a single database and a single CLI entry point for all test types. Added faker to basic app dev requirements.
Used aliases for fixture directory definitions
new asset management WIP
new asset WIP [skip ci]
new asset WIP: renabled asset publishing
new asset WIP [skip ci]
Added `yii\composer\Installer::postCreateProject()` and modified the syntax of calling installer methods in composer.json [skip ci]
cleaned up the key so that it can be filled up with a random key automatically when installed.
Fixes #4914