follow yams api change: attributes permissions are now defined for an 'update' action, no more 'add' / 'delete' which makes no sense in such case. fix afs.relations_by_section permissions checking of object relation on the way.

usr/lib/python2.4/site-packages/cubicweb/
etc/init.d
etc/cubicweb.d
etc/bash_completion.d
usr/bin
usr/share/doc/cubicweb-ctl
var/run/cubicweb
var/log/cubicweb
var/lib/cubicweb/backup
var/lib/cubicweb/instances