RO scripts added. Also possible now to create privileged containers

 - SETTINGS files in template and riftware were modified to allow option for privileged container
 - New function in common/container to create privileged containers
 - RO SETTINGS and start_build skeleton were created

Change-Id: I80143214708e65c62c899efecd30d4b84fb715ce
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>