ls-tree: major rewrite to do pathspec

git-ls-tree should be rewritten to use a pathspec the same way everybody
else does. Right now it's the odd man out: if you do

	git-ls-tree HEAD divers/char drivers/

it will show the same files _twice_, which is not how pathspecs in general
work.

How about this patch? It breaks some of the git-ls-tree tests, but it
makes git-ls-tree work a lot more like other git pathspec commands, and it
removes more than 150 lines by re-using the recursive tree traversal (but
the "-d" flag is gone for good, so I'm not pushing this too hard).

		Linus
diff --git a/tree.h b/tree.h
index 9975e88..768e5e9 100644
--- a/tree.h
+++ b/tree.h
@@ -35,4 +35,13 @@
 /* Parses and returns the tree in the given ent, chasing tags and commits. */
 struct tree *parse_tree_indirect(const unsigned char *sha1);
 
+#define READ_TREE_RECURSIVE 1
+typedef int (*read_tree_fn_t)(unsigned char *, const char *, int, const char *, unsigned int, int);
+
+extern int read_tree_recursive(void *buffer, unsigned long size,
+			const char *base, int baselen,
+			int stage, const char **match,
+			read_tree_fn_t fn);
+
+
 #endif /* TREE_H */