`stub' sub-attribute added to cfg attribute @ lib/LDAP_CRUD.pm; authorizedService sub-attribute is amended

add service account related stuff lib/UMI/Controller/SearchBy.pm

service account branch and leaves related stuff moved to dedicated subroutines create_account_branch() and create_account_branch_leaf() lib/UMI/Controller/User.pm

new files added:
 lib/UMI/Form/AddServiceAccount.pm
 root/src/user/user_add_svc.tt
 root/src/user/user_preferences.tt
 root/static/images/avatar-mgmnt.png
 root/static/images/avatar-xmpp.png
Merge branch 'master' of ssh://github.com/z-eos/umi