Feature/add jmh samples 10 31

A few of notes:

* I followed the pattern used by the first sample and did not include the `main` method. A downside is that the recommended launch settings are missing as well as some analysis on what happens when the sample is executed. I think it may be a good idea to add the `main` methods in the future.

* I did not include sample 25 as it doesn't make sense without the `main` method (it's about programmatically invoking the runner with various settings).

* I kept the examples as close to the original ones as possible. This means that I used vars in a few places where I would normally use vals and I didn't change the Java collections to Scala collections. Depending on the goals, one could change that (but hopefully in a separate PR).