Merge origin.

debian/upstream/metadata

@@ -1,4 +1,6 @@
 Name: dulwich
 Repository: https://www.dulwich.io/code/
 Repository-Browse: https://www.dulwich.io/code/
+Bug-Database: https://github.com/dulwich/dulwich/issues
+Bug-Submit: https://github.com/dulwich/dulwich/issues/new
 Contact: https://groups.google.com/forum/#!forum/dulwich-discuss