Fixing porcelain's status documentation. (#708)

Fix porcelain's status documentation.

Staged is a dict with lists for each type of staged paths as it implements get_tree_changes(r).

dulwich/porcelain.py

@@ -930,7 +930,7 @@ def status(repo=".", ignored=False):
     :param repo: Path to repository or repository object
     :param ignored: Whether to include ignored files in `untracked`
     :return: GitStatus tuple,
-        staged -    list of staged paths (diff index/HEAD)
+        staged -  dict with lists of staged paths (diff index/HEAD)
         unstaged -  list of unstaged paths (diff index/working-tree)
         untracked - list of untracked, un-ignored & non-.git paths
     """