Move ldap setup to users module setup
This is to move the ldap server setup from freedombox-setup to plinth. The setup is done in the users module, which is an essential module so it will be run during "plinth --setup".
I also moved the ldapscripts configuration setup, so it doesn't need to be run every time we use ldapscripts.
No upgrade is needed for existing 0.9 systems, so I left the module version at 1.