Enable to pick the test class for load

e.g.
- Description
GIVEN I have a single class and single method
WHEN I pick the class
THEN I will be able to run that method for the load/stress

- Feature:
This will also run all methods in the class. Those methods(in case of more than one) will run sequentially. This feature might have an impact on the performance-testers to think that the methods will run in parallel.

- Solution:
Either allow this feature with a note or README updated.
OR
Warn the developer/programmer about the sequential behavior.

- Note-
This will be an additional feature only.
This is also already achieved in the `parallel runner` currently(JUnit4), for all the parallel users to do `their tasks in sequence` mimicking the production load/stress.

- So what's new?
Ans: Only syntactical sugar.