display scanning message whenever reconcileStaged has enough files to chew on

Clear visible progress bar first.

Removed showSideActionAfter because it can't be used in reconcileStaged
(import loop). Instead, it counts the number of files it
processes and displays it after it's seen a sufficient to know it's
taking a while.

Sponsored-by: Dartmouth College's Datalad project

Annex/WorkTree.hs

@@ -15,8 +15,6 @@ import Annex.Content
 import Annex.ReplaceFile
 import Annex.CurrentBranch
 import Annex.InodeSentinal
-import Annex.Concurrent
-import Utility.ThreadScheduler
 import Utility.InodeCache
 import Git.FilePath
 import Git.CatFile
@@ -81,7 +79,7 @@ ifAnnexed file yes no = maybe no yes =<< lookupKey file
  - as-is.
  -}
 scanAnnexedFiles :: Bool -> Annex ()
-scanAnnexedFiles initscan = showSideActionAfter oneSecond "scanning for annexed files" $ do
+scanAnnexedFiles initscan = do
 	-- This gets the keys database populated with all annexed files,
 	-- by running Database.Keys.reconcileStaged.
 	Database.Keys.runWriter (const noop)