* Use two kind of backends: a domain backend and account backend.
* Adapt the configuration for this change.
* Changed the backend loading system via Backend.get.
* Created two new namespaces: AccountBackend and DomainBackend.
* Split up the Backend::Basic class into AccountBackend::Basic and
DomainBackend.
* Removed the Server::Account class, moved the methods to
AccountBackend::Basic.
* Created the Htaccess AccountBackend, moved the LDAPv3 backend
to DomainBackend::Ldap.
* Removed AccountBackend related stuff from DomainBackend::Ldap.
git-svn-id: svn+ssh://svn.luon.net/svn/ildus/trunk@12 65a33f86-aa00-0410-91be-cd1bf5efb309