hash lxcname for use in monitor unix socket sun_path[108]

- Also convert to unix abstract socket
- A simple FNV hash is used instead of SHA-1 since we may not HAVE_GNUTLS

Signed-off-by: Dwight Engen <dwight.engen@oracle.com>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>