Add documentation how to replicate the test result

[00travelgirl00]

Add a documentation how to test.

A test result should be possible to replicate. Therefore it should be transparent how the test result was created.
Also for potential new contributor a workflow should be in place on how to test.

For example define:

• Testing environment (system + Version, Browser Version,..)
• Browser adons and personal settings on an device
• testing tool + manuell testing
• how to replicate the problem

As single components are testing, some informations my not be relevant, but it would be worth it, to document it, to be as transparent as possible and for onboarding new tester.