Appium Android UI tests for George App.

I've written here just 3 simple tests in the AuthorizationTest class which extends the BaseTest class. I'm going to declare all screens in the BaseTest class as lateinit variables and initialize the necessary screens in the appropriate classes where it needs. I also described 6 screens with parent BaseScreen.

List of things to do:

1. add some BDD framework
2. add the AppiumDriverService class which is going to start and configure the appium serve