If a target is linked against libraries with cmake
(target_link_libraries) and the libraries are not marked as PRIVATE
they are "exported" and in case a other target is linked against this
target it is also linked against *all* (not private) libraries.
Without declaring private libraries PRIVATE a lot of over linking
(linking against unneeded libraries) was done.
* Tests connection to not existing host (timeout)
* Tests connection to not exising host with abort.
* Tests connection to sfreerdp-server on localhost.