plumb creds from webapp to initremote

Avoids abusing setting environment variables, which was always a hack
and won't work on windows.

Assistant/WebApp/Configurators/Local.hs

@@ -314,7 +314,7 @@ getFinishAddDriveR drive = go
 		remotename' <- liftAnnex $ getGCryptRemoteName u dir
 		makewith $ const $ do
 			r <- liftAnnex $ addRemote $
-				enableSpecialRemote remotename' GCrypt.remote $ M.fromList
+				enableSpecialRemote remotename' GCrypt.remote Nothing $ M.fromList
 					[("gitrepo", dir)]
 			return (u, r)
 	{- Making a new unencrypted repo, or combining with an existing one. -}