add initial SetChatFilterMessage packet and tests; gave FriendsResponse a valid action enumeration; changed continent id and building id in DensityUpdateLevel to use simple data type rather than PlanetSideGUID; worked these packet changes into WSA initialization workflow

common/src/test/scala/game/DensityLevelUpdateMessageTest.scala

@@ -49,4 +49,4 @@ class DensityLevelUpdateMessageTest extends Specification {
     val msg1 = DensityLevelUpdateMessage(1, 19999, List(0,0, 0,0, 0,-1, 0,0))
     PacketCoding.EncodePacket(msg1).isSuccessful mustEqual false
   }
-}
+}