Merged the int/long unification branch, by very crude means (sorry Thomas!).
I banged on the code (beyond what's in that branch) to make fewer tests fail;
the only tests that fail now are:
  test_descr -- can't pickle ints?!
  test_pickletools -- ???
  test_socket -- See python.org/sf/1619659
  test_sqlite -- ???
I'll deal with those later.
diff --git a/Python/traceback.c b/Python/traceback.c
index cfbd833..04078b9 100644
--- a/Python/traceback.c
+++ b/Python/traceback.c
@@ -250,7 +250,7 @@
 		return -1;
 	}
 	limitv = PySys_GetObject("tracebacklimit");
-	if (limitv && PyInt_Check(limitv)) {
+	if (limitv && PyInt_CheckExact(limitv)) {
 		limit = PyInt_AsLong(limitv);
 		if (limit <= 0)
 			return 0;