First pass at party service

AuroraCradle/Src/Protos/signal.proto

@@ -69,6 +69,13 @@ message PartyListItem {
 message ListPartiesRequest {
     int32 page_size = 1;
     string page_token = 2;
+    string order_by = 3;
+    SortDirection order_direction = 4;
+}
+
+enum SortDirection {
+    Asc = 0;
+    Desc = 1;
 }
 
 message ListPartiesResponse {