Traverser DFS/BFS pre/post order examples in Kotlin

[amatiushkin]

There few things which would be nice to have as part of this PR:

• example of how to import Traverser into Kotlin project
• sample code snippet which runs DFS/BFS pre/post order against example data set (for example company organization chart or bring your sample)

As one of practical suggestion -- StackOverflow or some other forum might have a question about traversing something in mobile app, this could be a good tasks which can be solved with traversal as well.

This task specify #16 for @qbool

[abhishekganesan]

@amatiushkin

[stong2351]

Is this assigned to anyone yet? if not I'm interested

[altfix]

Yes it's assigned to me. Although you can implement these using Scala see #16

[stong2351]

Cool, I just responded to that thread. I'd be willing to use Scala

[vaggarwal2]

I would like to add it in Kotlin.

[vaggarwal2]

Looks like a PR is already raised for it. I can work in Groovy.