Workaround bug 936

Apply a workaround for bug 936 that shortens the vnf and vdu id to no more than 12 characters, to keep the application name under the juju limit of 50 characters

Change-Id: I2bb49032f9f3432d304139b6e6b5ae0f62dc2a2a
Signed-off-by: Adam Israel <adam.israel@canonical.com>