Move to use interfaces, that will let us later add tests that will
verify that all the correct logging is performed. As an example, added a
test for XmlResultParser that ensures that the failures are correctly
generated. The test uses Moq to pass the different paths to be used and
later be able to verify the wirtten xml.
Co-authored-by: Přemek Vysoký <premek.vysoky@microsoft.com>
Manuel de la Pena