* Updated gradle to 6.7
* Updated AGP to 4.1.0 and infer lint from the agp version.
* Suppress the UnstableApiUsage on the lint tests.
* Added a test case where private change handler extends a base class that extends from the ControllerChangeHandler.
* Fixed the test case by checking the all super classes.
* Added a controller stub for the controleller detector tests.
* Added a testcase for when a controller has a base class.
* Added a testcase for when a controller has a base class.
* Accept licenses before installing for travis.
* Attempt to not add the android components.
* Removed the licenses command.
* Added the preview license too.
* Introduce kotlin and converted the ControllerChangeType to kotlin.
* Migrated the ThreadUtils to kotlin.
* Migrated the TransactionIndexer to kotlin.
* Migrated the ChangeHandlerFrameLayout to kotlin.
* Migrated Conductor to kotlin.
* Added RestrictTo annotations.
* Migrated the RouterRequiringFunc to kotlin.
* Migrated the RouterTransaction to kotlin
* Make use of diamonds.
* Make use of lambdas and method references.
* Use an interface with default implementations for the LifecycleListener.
* Simplify the attachRouter function.
* Updated the code style and checkin the idea folder.
* Use a Controller extension function for the router transaction.
* Use let's instead of forced !! casts.
* Added default implementations of ControllerChangeListener
* Migrated the NoOpControllerChangeHandler to kotlin.
* Use a top level extension function for the asTransaction function.
* Add JvmField annotations to the ControllerChangeType fields.
* Use the local variables instead of calling the controller again.
* Use Android Sdk 27
* Updated the unmock plugin and use the default configuration.
* Removed the explicit buildTools and use the one bundled with the plugin.
* Updated the support library, butterknife, leakCanary, rxjava 1 & 2,
rxlifecycle 1 & 2, junit and robolectric.
* Migrated the lint checks to UAST.
* Rename the UClass "declaration" to "field" to be consistent to the
other check and the default name.
* Moved the evaluator of the ControllerIssueDetector to the handler too.