Add REST API support to members

Members can be now retrieved one at a time is user has admin rights.
Implemented also permissions and throttle rates to REST API and added
required settings.py modifications to settings-sample.py file.

sikweb/settings-sample.py

@@ -137,6 +137,7 @@ REST_FRAMEWORK = {
     'DEFAULT_PERMISSION_CLASSES': (
         'rest_framework.permissions.IsAuthenticated',
         'rest_framework.permissions.DjangoModelPermissions',
+        'rest_framework.permissions.IsAdminUser',
     ),
     'DEFAULT_THROTTLE_CLASSES': (
         'members.throttles.BurstRateThrottle',