add current fn to nih_error msgs

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>

Conflicts:
	cgmanager.c
proxy: set up disconnection handler

Re-try connection when the cgmanager has gone away (and hopefully
restarted).

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>