Nova: add iproute package to images

This PS adds the `ip` command to images, which is used during network
setup of VM's.

Change-Id: Iaccef74719779e85780f1f8f5385cc5f09671873

centos/Dockerfile

@@ -14,6 +14,7 @@ ADD $OVERRIDE /
 RUN set -x \
     && yum upgrade -y \
     && yum install -y git \
+        iproute \
         libpython2.7 \
         libvirt0 \
         libxml2 \

debian/Dockerfile

@@ -16,6 +16,7 @@ RUN set -x \
     && apt-get dist-upgrade -y \
     && apt-get install -y --no-install-recommends git \
         ca-certificates \
+        iproute2 \
         libpython2.7 \
         libvirt0 \
         libxml2 \

ubuntu/Dockerfile

@@ -16,6 +16,7 @@ RUN set -x \
     && apt-get dist-upgrade -y \
     && apt-get install -y --no-install-recommends git \
         ca-certificates \
+        iproute2 \
         libpython2.7 \
         libvirt0 \
         libxml2 \