drop incremental json object display; clean up code

This gets rid of quite a lot of ugly hacks around json generation.

I doubt that any real-world json parsers can parse incomplete objects, so
while it's not as nice to need to wait for the complete object, especially
for commands like `git annex info` that take a while, it doesn't seem worth
the added complexity.

This also causes the order of fields within the json objects to be
reordered. Since any real json parser shouldn't care, the only possible
problem would be with ad-hoc parsers of the old json output.

Utility/JSONStream.hs

@@ -1,80 +0,0 @@
-{- Streaming JSON output.
- -
- - Copyright 2011, 2016 Joey Hess <id@joeyh.name>
- -
- - License: BSD-2-clause
- -}
-
-{-# LANGUAGE GADTs, OverloadedStrings #-}
-
-module Utility.JSONStream (
-	JSONChunk(..),
-	start,
-	add,
-	addNestedObject,
-	end
-) where
-
-import Data.Aeson
-import qualified Data.Text as T
-import qualified Data.ByteString.Lazy as B
-import qualified Data.ByteString.Lazy.UTF8 as BU8
-import Data.Char
-import Data.Word
-
-data JSONChunk v where
-	AesonObject :: Object -> JSONChunk Object
-	JSONChunk :: ToJSON v => [(String, v)] -> JSONChunk [(String, v)]
-
-encodeJSONChunk :: JSONChunk v -> B.ByteString
-encodeJSONChunk (AesonObject o) = encode o
-encodeJSONChunk (JSONChunk l) = encode $ object $ map mkPair l
-  where
-	mkPair (s, v) = (T.pack s, toJSON v)
-
-{- Aeson does not support building up a larger JSON object piece by piece
- - with streaming output. To support streaming, a hack:
- - The final "}" is left off the JSON, allowing more chunks to be added
- - to later. -}
-start :: JSONChunk a -> B.ByteString
-start a
-	| not (B.null b) && B.last b == endchar = B.init b
-	| otherwise = bad b
-  where
-	b = encodeJSONChunk a
-
-add :: JSONChunk a -> B.ByteString
-add a
-	| not (B.null b) && B.head b == startchar = 
-		B.cons addchar (B.drop 1 b)
-	| otherwise = bad b
-  where
-	b = start a
-
-addNestedObject :: String -> B.ByteString -> B.ByteString
-addNestedObject s b = B.concat
-	[ ",\""
-	, BU8.fromString s
-	, "\":"
-	, b
-	, "}"
-	]
-
-end :: B.ByteString
-end = endchar `B.cons` sepchar `B.cons` B.empty
-
-startchar :: Word8
-startchar = fromIntegral (ord '{')
-
-endchar :: Word8
-endchar = fromIntegral (ord '}')
-
-addchar :: Word8
-addchar = fromIntegral (ord ',')
-
-sepchar :: Word8
-sepchar = fromIntegral (ord '\n')
-
-bad :: B.ByteString -> a
-bad b = error $ "JSON encoder generated unexpected value: " ++ show b
-