fix some mixed space+tab indentation

This fixes all instances of " \t" in the code base. Most common case
seems to be after a "where" line; probably vim copied the two space layout
of that line.

Done as a background task while listening to episode 2 of the Type Theory
podcast.

CmdLine/GitAnnexShell.hs

@@ -66,7 +66,7 @@ options = commonOptions ++
 		check u = unexpectedUUID expected u
 	checkGCryptUUID expected = check =<< getGCryptUUID True =<< gitRepo
 	  where
-	  	check (Just u) | u == toUUID expected = noop
+		check (Just u) | u == toUUID expected = noop
 		check Nothing = unexpected expected "uninitialized repository"
 		check (Just u) = unexpectedUUID expected u
 	unexpectedUUID expected u = unexpected expected $ "UUID " ++ fromUUID u