Merge branch 'pk/rebase-in-c-6-final'

The final step of rewriting "rebase -i" in C.

* pk/rebase-in-c-6-final:
  rebase: default to using the builtin rebase

builtin/rebase.c

@@ -55,7 +55,7 @@ static int use_builtin_rebase(void)
 	cp.git_cmd = 1;
 	if (capture_command(&cp, &out, 6)) {
 		strbuf_release(&out);
-		return 0;
+		return 1;
 	}
 
 	strbuf_trim(&out);