Discover openhome devices with Product:3 service (#232)

Author: Barry Williams

netdisco/discoverables/openhome.py

@@ -7,4 +7,5 @@ class Discoverable(SSDPDiscoverable):
 
     def get_entries(self):
         """Get all the Openhome compliant device uPnP entries."""
-        return self.find_by_st("urn:av-openhome-org:service:Product:2")
+        return self.find_by_st("urn:av-openhome-org:service:Product:2") + \
+            self.find_by_st("urn:av-openhome-org:service:Product:3")