Simon 3.6.4 released

When I added recognition of version 4 groups in version 3.6.2, I did so for tests, but services, filters, notifiers and reports can also have groups in version 4. So here's Simon 3.6.4 to fix an issue with editing those.

If you're using OS X 10.10 (Yosemite), I recommend that you upgrade to version 4, if you haven't already. It includes heaps of great improvements. But if you're on 10.6 (Snow Leopard) to 10.9 (Mavericks), you can download Simon 3.6.4 now.