lnrpc+lncli: add feature bits to GetInfo

lnrpc/rpc.proto

@@ -1539,6 +1539,12 @@ message GetInfoResponse {
 
     // Whether we consider ourselves synced with the public channel graph.
     bool synced_to_graph = 18 [json_name = "synced_to_graph"];
+
+    /*
+    Features that our node has advertised in our init message, node
+    announcements and invoices.
+    */
+    map<uint32, Feature> features = 19 [json_name = "features"];
 }
 
 message Chain {

lnrpc/rpc.swagger.json

@@ -2504,6 +2504,13 @@
           "type": "boolean",
           "format": "boolean",
           "description": "Whether we consider ourselves synced with the public channel graph."
+        },
+        "features": {
+          "type": "object",
+          "additionalProperties": {
+            "$ref": "#/definitions/lnrpcFeature"
+          },
+          "description": "Features that our node has advertised in our init message, node\nannouncements and invoices."
         }
       }
     },