Remove unnecessary methods in LTTng Tracer Control model

Remove unnecessary methods in LTTng Tracer Control model

In many classes of the LTTng Tracer Control model convenience
methods exists that don't require passing a progress monitor and
that just calls another methods to pass a NullProgressMontior
instance. This causes increased maintenance work and doesn't bring
much gain.

Change-Id: Iae4c38d994953ead656dffc7065f01168dbbc7a7
Signed-off-by: Bernd Hufmann <bhufmann@gmail.com>
Reviewed-on: https://git.eclipse.org/r/10732
Tested-by: Hudson CI
Reviewed-by: Alexandre Montplaisir <alexmonthy@voxpopuli.im>
IP-Clean: Alexandre Montplaisir <alexmonthy@voxpopuli.im>
Tested-by: Alexandre Montplaisir <alexmonthy@voxpopuli.im>