Add new step that allows to randomly pick one of predefined values

[pawelWritesCode]

Background

gdutils is library with useful method for testing HTTP(s) API.

Objective

Create new method that allows to randomly pick one of predefined values.

For example, cucumber wrapper of such method may look like this

Given I pick randomly one "(string|int|float64)" of "value1|value2|value3"

Creator of such method should pre-define separator used for different values passed in last argument (example uses |)