added codeception tests to frontend
modified buttons attributes to skip sf-crawler bug
added codeception to backend
added button attributes to skip sf-crawler bug
added codeception tests to common
added codeception main yaml
added codeception tests to console
added index tests files to application
added guide notes
newlines fixed, code-guy deleted
improved dependencies, guide
removed ordered list
formatting improved
correct lists fixed
Mild edits
Edited the intro and first section
Use 'Yii::$app->request->post()' instead of $_POST
Merge pull request #2457 from Theill11/update-gii-templates

Use 'Yii::$app->request->post()' instead of $_POST
small code style fix
updated apidoc composer.json

to require newly released stable version of phpdoc reflection library