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.

Logs/Schedule.hs

@@ -35,7 +35,7 @@ scheduleSet uuid@(UUID _) activities = do
 	Annex.Branch.change scheduleLog $
 		showLog id . changeLog ts uuid val . parseLog Just
   where
-  	val = fromScheduledActivities activities
+	val = fromScheduledActivities activities
 scheduleSet NoUUID _ = error "unknown UUID; cannot modify"
 
 scheduleMap :: Annex (M.Map UUID [ScheduledActivity])