BUG-459 Remove deprecated NetconfClient class.

NetconfClient moved to test sources, now will be used only by tests.

Change-Id: Ia98abe3f6fa4f05566b71d57c519c2149726bcb6
Signed-off-by: Maros Marsalek <mmarsale@cisco.com>
Merge "BUG-459 Remove deprecated NetconfClient class."