Add a macaddr if precisely one veth is specified but no hwaddr.  Allow
specifying ssh authkeys.  In cloud template, copy locales by default and allow
a tarball to be specified.
Signed-off-by: Ben Howard <ben.howard@canonical.com>
Signed-off-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>