Documentation of the DSL

[dbaelz]

Use KDoc in the Code and the Dokka tool to create a documentation for the library DSL.

TODO

• Code documentation with KDoc
• Use Dokka Gradle task to generate the documentation

[dbaelz]

There are some issues with Dokka in combination with Kotlin/Native and multiplatform projects. Therefore, I've changed the TODO and just merge the created KDoc. We should add the Dokka late when they are fixed.

Issues

• KotlinNullPointerException when running gradle task in kotlin2js project Kotlin/dokka#212: KotlinNullPointerException for kotlin2js (and other multiplatform) projects, when using a version above 0.9.14
• dokka Gradle plugin doesn't work with Kotlin 1.2 Kotlin/dokka#265: Bug with the Gradle plugin fixed in 0.9.17

Due the first issue, we can't 0.9.17. Maybe this could be fixed, when we only use Dokka for the JVM target or in a JVM Gradle module. Yet another thing to take a look in the future.