Fixex to allow example to compile (v2 embedding, kotlin gradle wrapper, wrapper and compilesdk)

[FrankDomburg]

Various fixes for compiling the example

• Android v2 embedding
• Kotlin Gradle Plugin
• Gradle wrapper
• Compile SDK to 31

[FrankDomburg]

Guess I did something wrong in the Editor. These two commits are different. The first ones fixes all sorts of compilation errors for the example. The second one fixes all sort of lint issues.

[letsar]

Thanks for the PR but I close it this since I updated the Android project of the example