Removed commented out getType test call, as the test is not implemented in such a way to test all formats.

Changed TYPED_TEST_CASE to TYPED_TEST_SUITE, as per google test recommendation which said that TYPED_TEST_CASE is deprecated.

They are not suitable for more than 2 devices/execution types; their design
breaks the Open-Closed Principle. Instead, a type template "Self" was
created, which allows to change any template parameter.

This is necessary to be able to run tests in parallel.

fixes #13