Temporary changes to the Last Heard page

The Last Heard page is currently only showing local traffic inside the PRN system.  External talk groups, such as TAC 310 and DCI Bridge, are no longer showing.  This was done because the constant kerchunks from hotspots and Brandmeister were pushing our local traffic off the screen.

Eventually I hope to have two sections, one for our local traffic, and another below it for external traffic.