make span names more generic by using OriginalURL instead of Path

example/main.go

@@ -51,6 +51,7 @@ func main() {
 	})
 
 	main.Get("/", Handler)
+	main.Get("/just/some/more/complex/path/:with/params", Handler)
 
 	// handle interrupts (shutdown)
 	c := make(chan os.Signal, 1)

example/requests.hurl

@@ -1,2 +1,5 @@
 GET http://127.0.0.1:3344/
-HTTP 200
+HTTP 500
+
+GET http://127.0.0.1:3344/just/some/more/complex/path/:with/params
+HTTP 500