[ldapfeed] use LDAP_SCOPES to find user-scope We already have LDAP_SCOPES dict defining possible scopes, this avoid possible code injection from config... Thus we can drop global variables already defined in LDAP_SCOPES since they are not used directly anymore.

[ldapfeed] drop now useless import from __future__

[rdf] Add a basic foaf adapter for CWUser By the way, use RDFLib namespaces