Use ReactiveSearch without default styling applied

**Affected Projects**
React

**Is your feature request related to a problem? Please describe.**
I want to be able to use ReactiveSearch without any base styling applied. I don't want to be overwriting and resetting styles every time i include a new ReactiveSearch component.

**Describe the solution you'd like**
It would be nice to have a version of the library available without any default classes/styling applied.

**Describe alternatives you've considered**
I have tried using the className properties but the original class names and styling remain present on the element.

Review the React package's default styling and className behavior described in the issue. Determine the scope of a styling-free library variant and how existing components would opt into it. Done means users can use ReactiveSearch without base classes or styling while retaining the requested custom className behavior.

Written by the indexing model from the issue text.