Fix some comments.

britney.conf

@@ -102,7 +102,7 @@ ADT_SHARED_RESULTS_CACHE =
 # Swift base URL with the results (must be publicly readable and browsable)
 # or file location if results are pre-fetched
 ADT_SWIFT_URL     = https://objectstorage.prodstack4-5.canonical.com/v1/AUTH_77e2ada1e7a84929a74ba3b87153c0ac
-# Swift username that should have exclusive read rights to the test results
+# Swift identity with read access to the private result container
 # (this is required whenever a private PPA is used for testing)
 ADT_SWIFT_USER    = 
 ADT_SWIFT_PASS    = 

britney.conf.template

@@ -124,7 +124,7 @@ ADT_SHARED_RESULTS_CACHE =
 # or file location if results are pre-fetched
 #ADT_SWIFT_URL     = https://example.com/some/url
 ADT_SWIFT_URL     = file:///path/to/britney/state/debci.json
-# Swift username that should have exclusive read rights to the test results
+# Swift identity with read access to the private result container
 # (this is required whenever a private PPA is used for testing)
 ADT_SWIFT_USER    = 
 ADT_SWIFT_PASS    = 

britney2/policies/autopkgtest.py

@@ -202,7 +202,7 @@ class AutopkgtestPolicy(BasePolicy):
 
         # log into swift in case we need to fetch some private results
         # this is optional - if there are no credentials present, results will
-        # be fetched the traditional way
+        # be fetched without authentication
         if self.options.adt_swift_user:
             if (not self.options.adt_swift_pass or
                     not self.options.adt_swift_auth_url or