Improved unit tests organisation and better testing for dcStream.

Change-Id: I4a4a42b8faa853fe4e706890444d8a30efeadd10
Code review: patchset #1.

Change-Id: I9d525727c16bd0aa2b940d01e1f75ea33648ed31
Merge pull request #50 from rdumusc/unit_tests_refactoring

Improved unit tests organisation and better testing for dcStream.