[entities] Optimize CWUser.properties. This property gets called each time a user connects to a repository, which means a lot. This optimisation cuts its execution time by 5 according to my tests

etc/init.d
etc/cubicweb.d
etc/bash_completion.d
usr/bin
usr/share/doc/cubicweb-ctl
var/log/cubicweb
var/lib/cubicweb/backup
var/lib/cubicweb/instances