Document Kotlin usage

[kurtisnelson]

The sample app has a kotlin activity consuming the library, document why this library is not in kotlin.

[kawpiya]

@kurtisnelson Can I please know why the library is not in Kotlin?

[kurtisnelson]

Storage requires using fundamental JVM IO APIs, Kotlin gives no benefit and adds overhead. The library itself is designed to be consumed from Kotlin and feel native.
Kotlin gives no benefit in this situation.

[kawpiya]

Cannot we have syntax improvement with Kotlin? (extension functions, DSL)