Lots more refactoring, finish add node (and almost the location updating)

backend/telemetry/src/aggregator/mod.rs

@@ -0,0 +1,8 @@
+mod aggregator;
+mod inner_loop;
+mod find_location;
+
+// Expose the various message types that can be worked with externally:
+pub use inner_loop::{ FromFeedWebsocket, FromShardWebsocket, ToFeedWebsocket, ToShardWebsocket };
+
+pub use aggregator::*;