Add a type-safe Kotlin configuration builder API

[jvz]

Using the functionality in https://kotlinlang.org/docs/type-safe-builders.html it should be fairly straightforward to make a Kotlin-specific DSL similar to the ConfigurationBuilder Java API.

[adwsingh]

@jvz is this meant to be an issue in https://github.com/apache/logging-log4j-kotlin ?

[jvz]

This could end up there, yeah.

[jvz]

@jvz is this meant to be an issue in https://github.com/apache/logging-log4j-kotlin ?

Good idea. Transferred.

[rocketraman]

Is this a dup of #36 or vice-versa?

[ppkarwasz]

@rocketraman,

#36 is about the LogBuilder interface, this issue is about ConfigurationBuilder.

[rocketraman]

@rocketraman,

#36 is about the LogBuilder interface, this issue is about ConfigurationBuilder.

Thanks for the clarification.