Revert ServerAliveInterval

Revert ServerAliveInterval change in 6.20161111, which caused problems
with too many old versions of ssh and unusual ssh configurations.

It should have not been needed anyway since ssh is supposted to
have TCPKeepAlive enabled by default.

Annex/Ssh.hs

@@ -33,7 +33,6 @@ import qualified Git.Url
 import Config
 import Annex.Path
 import Utility.Env
-import Utility.Tmp
 import Types.CleanupActions
 import Git.Env
 #ifndef mingw32_HOST_OS
@@ -50,37 +49,13 @@ sshOptions (host, port) gc opts = go =<< sshCachingInfo (host, port)
 	go (Just socketfile, params) = do
 		prepSocket socketfile
 		ret params
-	ret ps = do
-		overideconfigfile <- fromRepo gitAnnexSshConfig
-		-- We assume that the file content does not change.
-		-- If it did, a more expensive test would be needed.
-		liftIO $ unlessM (doesFileExist overideconfigfile) $
-			viaTmp writeFile overideconfigfile $ unlines
-				-- Make old version of ssh that does
-				-- not know about Include ignore those
-				-- entries.
-				[ "IgnoreUnknown Include"
-				-- ssh expands "~"
-				, "Include ~/.ssh/config"
-				-- ssh will silently skip the file
-				-- if it does not exist
-				, "Include /etc/ssh/ssh_config"
-				-- Everything below this point is only
-				-- used if there's no setting for it in
-				-- the above files.
-				--
-				-- Make sure that ssh detects stalled
-				-- connections.
-				, "ServerAliveInterval 60"
-				]
-		return $ concat
-			[ ps
-			, [Param "-F", File overideconfigfile]
-			, map Param (remoteAnnexSshOptions gc)
-			, opts
-			, portParams port
-			, [Param "-T"]
-			]
+	ret ps = return $ concat
+		[ ps
+		, map Param (remoteAnnexSshOptions gc)
+		, opts
+		, portParams port
+		, [Param "-T"]
+		]
 
 {- Returns a filename to use for a ssh connection caching socket, and
  - parameters to enable ssh connection caching. -}