Perform Concept Checking in Tests

[fmoessbauer]

Many of the DASH classes are implementations of concepts. In the past, there were many bugs related to an inconsistent or incomplete implementation. To fix this in a generic and support reducing manner, I propose testing the concepts.

Fortunately googletest supports this type of test by using typed tests. There is also an hint on how to use this for concept checking.

Then, we could also use the traits (e.g. pattern traits) to select which tests are run for a given type.

Maybe that's also a candidate for a student project.