Move all output through StatusOutput

Write log output through StatusOutput so that the status implementation
can synchronize it with its own output.

Test: status_test.go
Change-Id: I917bdeeea4759a12b6b4aa6d6d86ee18a2771723

ui/terminal/dumb_status.go

@@ -64,3 +64,8 @@ func (s *dumbStatusOutput) FinishAction(result status.ActionResult, counts statu
 }
 
 func (s *dumbStatusOutput) Flush() {}
+
+func (s *dumbStatusOutput) Write(p []byte) (int, error) {
+	fmt.Fprint(s.writer, string(p))
+	return len(p), nil
+}