fountain.ldap: Only use RESTARTABLE connection for remote hosts

The `client_strategy=RESTARTABLE` causes issues with local LDAP
servers, such as ldaptor, which might be used for testing purposes.

fountain/ldap.py

 # -*- coding: utf-8 -*-
 from __future__ import unicode_literals
 import ssl
-from ldap3 import Server, Connection, RESTARTABLE, DSA
+from ldap3 import Server, Connection, DSA, RESTARTABLE
 from ldap3.core.tls import Tls
 from ldap3.utils.uri import parse_uri
 from django.conf import settings
@@ -44,15 +44,17 @@ class Ldap(object):
             server_kwargs['get_info'] = DSA
             
         s=Server(**server_kwargs)
-        c = Connection(
-            s,
-            auto_bind=True,
-            user=self.LDAP_SYNC_BASE_USER,
-            password=self.LDAP_SYNC_BASE_PASS,
-            # Make the connection reusable
-            client_strategy=RESTARTABLE,
-        )
-        return c
+        
+        connection_kwargs = {
+            'server': s,
+            'auto_bind': True,
+            'user': self.LDAP_SYNC_BASE_USER,
+            'password': self.LDAP_SYNC_BASE_PASS,
+        }
+        if self.LDAP_PARAMS['host'] != 'localhost':
+            connection_kwargs['client_strategy'] = RESTARTABLE
+        
+        return Connection(**connection_kwargs)
 
     def get_attributes(self, username):
         conn = self.connection