Updated Dockerfiles and postinst for RO and LCM to use pip-9.0.3

Also replaces apt by apt-get in Dockerfiles

Change-Id: I54c8c45745e0550878d05f3c386ea7d633b50786
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>
diff --git a/lcm/Dockerfile b/lcm/Dockerfile
index 698ec9c..06a0fcd 100644
--- a/lcm/Dockerfile
+++ b/lcm/Dockerfile
@@ -11,6 +11,7 @@
     python3-stdeb python3-setuptools python3-all python-all \
     python3-bitarray python3-regex python3-lxml debhelper dh-python tox wget \
     python3-cffi \
+    && pip3 install pip==9.0.3 \
     && pip3 install -U aiokafka pyang lxml six enum34
 
 RUN git clone https://osm.etsi.org/gerrit/osm/N2VC.git \