scripts: add __init__.py file to scripts/qmp/

When searching for modules to load, python will ignore any
sub-directory which does not contain __init__.py. This means
that both scripts and scripts/qmp/ have to be explicitly added
to the python path. By adding a __init__.py file to scripts/qmp,
we only need add scripts/ to the python path and can then simply
do 'from qmp import qmp' to load scripts/qmp/qmp.py.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Message-Id: <1469020993-29426-2-git-send-email-berrange@redhat.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>