added a couple of new test cases
added some new test cases
added descriptions for new test cases
added more test cases for Android's application object and its lifecycle
updated application lifecycle examples
update
added some more test cases:

- Code obfuscation through shadowing system classes
- Callback deregistration
- Callback ordering test
- Global callbacks
fixed a typo
added test cases for reflection
added two new test cases
added a new test case: Callbacks_Button3
added new gif
updated readme
updated readme
updated readme