type based git config handling

Now there's a Config type, that's extracted from the git config at startup.
Note that laziness means that individual config values are only looked up
and parsed on demand, and so we get implicit memoization for all of them.
So this is not only prettier and more type safe, it optimises several
places that didn't have explicit memoization before. As well as getting rid
of the ugly explicit memoization code.

Not yet done for annex.<remote>.* configuration settings.

Annex/Content.hs

@@ -35,7 +35,6 @@ import System.IO.Unsafe (unsafeInterleaveIO)
 import Common.Annex
 import Logs.Location
 import qualified Git
-import qualified Git.Config
 import qualified Annex
 import qualified Annex.Queue
 import qualified Annex.Branch
@@ -188,7 +187,7 @@ withTmp key action = do
  - in a destination (or the annex) printing a warning if not. -}
 checkDiskSpace :: Maybe FilePath -> Key -> Integer -> Annex Bool
 checkDiskSpace destination key alreadythere = do
-	reserve <- getDiskReserve
+	reserve <- annexDiskReserve <$> Annex.getConfig
 	free <- liftIO . getDiskFree =<< dir
 	force <- Annex.getState Annex.force
 	case (free, keySize key) of
@@ -396,11 +395,8 @@ saveState :: Bool -> Annex ()
 saveState nocommit = doSideAction $ do
 	Annex.Queue.flush
 	unless nocommit $
-		whenM alwayscommit $
+		whenM (annexAlwaysCommit <$> Annex.getConfig) $
 			Annex.Branch.commit "update"
-  where
-	alwayscommit = fromMaybe True . Git.Config.isTrue
-		<$> getConfig (annexConfig "alwayscommit") ""
 
 {- Downloads content from any of a list of urls. -}
 downloadUrl :: [Url.URLString] -> FilePath -> Annex Bool

Annex/Queue.hs

@@ -17,7 +17,6 @@ import Common.Annex
 import Annex hiding (new)
 import qualified Git.Queue
 import qualified Git.UpdateIndex
-import Config
 
 {- Adds a git command to the queue. -}
 addCommand :: String -> [CommandParam] -> [FilePath] -> Annex ()
@@ -55,11 +54,9 @@ get = maybe new return =<< getState repoqueue
 
 new :: Annex Git.Queue.Queue
 new = do
-	q <- Git.Queue.new <$> queuesize
+	q <- Git.Queue.new . annexQueueSize <$> getConfig
 	store q
 	return q
-  where
-	queuesize = readish <$> getConfig (annexConfig "queuesize") ""
 
 store :: Git.Queue.Queue -> Annex ()
 store q = changeState $ \s -> s { repoqueue = Just q }

Annex/Ssh.hs

@@ -18,9 +18,8 @@ import Common.Annex
 import Annex.LockPool
 import Annex.Perms
 #ifndef WITH_OLD_SSH
-import qualified Git.Config
-import Config
 import qualified Build.SysConfig as SysConfig
+import qualified Annex
 #endif
 
 {- Generates parameters to ssh to a given host (or user@host) on a given
@@ -60,8 +59,7 @@ sshInfo (host, port) = ifM caching
 	caching = return False
 #else
 	caching = fromMaybe SysConfig.sshconnectioncaching 
-		. Git.Config.isTrue
-		<$> getConfig (annexConfig "sshcaching") ""
+		. annexSshCaching <$> Annex.getConfig
 #endif
 
 cacheParams :: FilePath -> [CommandParam]