Improved log message to display URL as well.

Signed-off-by: Lucas Carvalho <lucas@nexedi.com>

src/zc/buildout/networkcache.py

@@ -99,8 +99,8 @@ def get_sha256sum_from_networkcached(network_cache, url, logger):
           return json.loads(result.read().strip()).get('sha256sum', None)
         logger.info('The url is not cached yet: %s' % url)
     except IOError, e:
-        logger.info('An error occurred to get sha256sum from networkcached:' \
-                                                               ' %s' % str(e))
+        logger.info('An error occurred to get sha256sum of url %s. %s' % \
+                                                               (url, str(e)))
 
 
 def download_network_cached(network_cache, path, url, logger):