fixup! download: verify checksum of downloaded data

slapos/libnetworkcache.py

@@ -94,7 +94,7 @@ class CheckResponse(object):
       self._sha512sum.update(r)
     elif amt != 0 and self._expected != self._sha512sum.hexdigest():
       raise NetworkcacheException(
-            'Failed to upload data to SHACACHE Server: invalid checksum.')
+            'Failed to download data to SHACACHE Server: invalid checksum.')
     return r
 
 class NetworkcacheClient(object):