avoid using removePathForcibly everywhere, it is unsafe

If the temp directory can somehow contain a hard link, it changes the
mode, which affects all other hard linked files. So, it's too unsafe
to use everywhere in git-annex, since hard links are possible in
multiple ways and it would be very hard to prove that every place that
uses a temp directory cannot possibly put a hard link in it.

Added a call to removeDirectoryForCleanup to test_crypto, which will
fix the problem that commit 17b20a2450
was intending to fix, with a much smaller hammer.

Sponsored-by: Dartmouth College's Datalad project

Test.hs

@@ -1794,7 +1794,12 @@ test_crypto = do
 		-- it needs to be able to store the agent socket there,
 		-- which can be problimatic when testing some filesystems.
 		absgpgtmp <- fromRawFilePath <$> absPath (toRawFilePath gpgtmp)
-		testscheme' scheme absgpgtmp
+		res <- testscheme' scheme absgpgtmp
+		-- gpg may still be running and would prevent
+		-- removeDirectoryRecursive from succeeding, so
+		-- force removal of the temp directory.
+		liftIO $ removeDirectoryForCleanup gpgtmp
+		return res
 	testscheme' scheme absgpgtmp = intmpclonerepo $ do
 		-- Since gpg uses a unix socket, which is limited to a
 		-- short path, use whichever is shorter of absolute