Make Service&File entries representation human-readable.

This will help in debugging and writing web-tests.

Change-Id: I748b19710f8590c6dee5e2e98e69aa8d74bb324a

metadataclient/v1/metadata_admin.py

@@ -12,6 +12,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 import StringIO
+import re
 from os.path import dirname, basename
 
 from metadataclient import exc
@@ -24,6 +25,14 @@ class Wrapper(object):
         for key, value in kwargs.items():
             setattr(self, key, value)
 
+    def __str__(self):
+        if '##' in self.id:
+            return re.sub(r'##', '/', self.id)
+        return self.id
+
+    def __repr__(self):
+        return 'RowWrapper({0})'.format(str(self))
+
 
 class Controller(object):
     def __init__(self, http_client):