Fixed "new messages" email alerts

There was a glitch that had gone unnoticed for a while causing extra "new messages" emails to get sent out.

The glitch was the time stamp of the last notice was not getting checked properly on chat room messages (private chat messages). This caused some users to get the same "new messages" email over and over. This didn't impact everyone so it went unnoticed for quite some time. But now that issue should be fixed and notices should only go out when there really are new messages added.

Now keep in mind, if new messages are added after one email goes out but before you visit the site, then you could still get another "new messages" email with updated message counts on the next notification cycle. But at least now it won't be the exact same email going out over and over.

So sorry that this one didn't get noticed sooner.