Restrict Unix socket file ownership by default to ug=rw

* default mode is now 0660 & ~umask
* chmod before chown: don't break apparmor profiles that didn't
  have `capability fowner` (which would be required now as chmod always
  triggers). This might lead to SUID and SGID bits getting cleared.

From: Stefan Bühler <stbuehler@web.de>

git-svn-id: svn://svn.lighttpd.net/spawn-fcgi/trunk@59 4a9f3682-ca7b-49a8-9a55-ba4640e46f83
Add example apparmor spawn-fcgi abstraction

From: Stefan Bühler <stbuehler@web.de>

git-svn-id: svn://svn.lighttpd.net/spawn-fcgi/trunk@60 4a9f3682-ca7b-49a8-9a55-ba4640e46f83