fixup! Fix performance regression and more precise tests.

Data/ByteString/Streaming/Char8.hs

@@ -734,7 +734,7 @@ w8IsSpace = \ !w8 ->
           || w == 0xa0 )  -- NBSP
 {-# INLINE w8IsSpace #-}
 
--- Try to position the stream at the next non-whitespace input, by
+-- | Try to position the stream at the next non-whitespace input, by
 -- skipping leading whitespace.  Only a /reasonable/ quantity of
 -- whitespace will be skipped before giving up and returning the rest
 -- of the stream with any remaining whitespace.  Limiting the amount of