Break ipaplatform / ipalib import cycle of hell

Here is an attempt to break the import cycle of hell between ipaplatform
and ipalib. All services now pass an ipalib.api object to
services.service(). RedHatServices.__init__() still needs to do a local
import because it initializes its wellknown service dict with service
instances.

Signed-off-by: Christian Heimes <cheimes@redhat.com>
Reviewed-By: Martin Basti <mbasti@redhat.com>

ipaserver/plugins/server.py

@@ -262,7 +262,7 @@ class server_mod(LDAPUpdate):
 
         if 'ipalocation_location' or 'ipaserviceweight' in options:
             self.add_message(messages.ServiceRestartRequired(
-                service=services.service('named').systemd_name,
+                service=services.service('named', api).systemd_name,
                 server=keys[0], ))
 
             result = self.api.Command.dns_update_system_records()