Merge branch 'en/combined-all-paths'

Output from "diff --cc" did not show the original paths when the
merge involved renames.  A new option adds the paths in the
original trees to the output.

* en/combined-all-paths:
  log,diff-tree: add --combined-all-paths option

diff.h

@@ -296,6 +296,7 @@ struct combine_diff_path {
 		char status;
 		unsigned int mode;
 		struct object_id oid;
+		struct strbuf path;
 	} parent[FLEX_ARRAY];
 };
 #define combine_diff_path_size(n, l) \