remove Utility.Conditional and use IfElse

This drops the >>! and >>? with the nice low fixity. IfElse does have
undocumented >>=>>! and >>=>>? operators, but I deem that too fishy.
Anyway, using whenM and unlessM is easier; I sometimes mixed the operators
up.

Remote/Bup.hs

@@ -69,7 +69,7 @@ bupSetup u c = do
 	-- bup init will create the repository.
 	-- (If the repository already exists, bup init again appears safe.)
 	showAction "bup init"
-	bup "init" buprepo [] >>! error "bup init failed"
+	unlessM (bup "init" buprepo []) $ error "bup init failed"
 
 	storeBupUUID u buprepo
 
@@ -167,9 +167,9 @@ storeBupUUID u buprepo = do
 	if Git.repoIsUrl r
 		then do
 			showAction "storing uuid"
-			onBupRemote r boolSystem "git"
-				[Params $ "config annex.uuid " ++ v]
-					>>! error "ssh failed"
+			unlessM (onBupRemote r boolSystem "git"
+				[Params $ "config annex.uuid " ++ v]) $
+					error "ssh failed"
 		else liftIO $ do
 			r' <- Git.Config.read r
 			let olduuid = Git.Config.get "annex.uuid" "" r'

Remote/Directory.hs

@@ -55,8 +55,8 @@ directorySetup u c = do
 	-- verify configuration is sane
 	let dir = fromMaybe (error "Specify directory=") $
 		M.lookup "directory" c
-	liftIO $ doesDirectoryExist dir
-		>>! error $ "Directory does not exist: " ++ dir
+	liftIO $ unlessM (doesDirectoryExist dir) $
+		error $ "Directory does not exist: " ++ dir
 	c' <- encryptionSetup c
 
 	-- The directory is stored in git config, not in this remote's

Remote/Rsync.hs

@@ -181,8 +181,8 @@ withRsyncScratchDir a = do
 	liftIO $ createDirectoryIfMissing True tmp
 	nuke tmp `after` a tmp
 	where
-		nuke d = liftIO $ 
-			doesDirectoryExist d >>? removeDirectoryRecursive d
+		nuke d = liftIO $ whenM (doesDirectoryExist d) $
+			removeDirectoryRecursive d
 
 rsyncRemote :: RsyncOpts -> [CommandParam] -> Annex Bool
 rsyncRemote o params = do