Making prefetcher call create_stores.

Fixes bug 888383

Change-Id: Ia3adc6a30f16f889cd344f8cb3fca4a071871fe4

glance/image_cache/prefetcher.py

@@ -28,6 +28,12 @@
 from glance.common import exception
 from glance.image_cache import ImageCache
 from glance import registry
+import glance.store
+import glance.store.filesystem
+import glance.store.http
+import glance.store.rbd
+import glance.store.s3
+import glance.store.swift
 from glance.store import get_from_backend
 
 
@@ -38,6 +44,7 @@ class Prefetcher(object):
 
     def __init__(self, options):
         self.options = options
+        glance.store.create_stores(options)
         self.cache = ImageCache(options)
         registry.configure_registry_client(options)