Address comments part 2

* OpenAPI Mock spec path adjusted
* Dropbox FileMetadata reflection refactored
* NaturalNumber type added

test/dropbox/docker-compose.yml

@@ -5,9 +5,11 @@ services:
     image: muonsoft/openapi-mock
     environment:
       OPENAPI_MOCK_USE_EXAMPLES: if_present
-      OPENAPI_MOCK_SPECIFICATION_URL: https://raw.githubusercontent.com/offen/docker-volume-backup/2ea59a649be79d6cb22b8b5ad29e24377d4ab9d4/test/dropbox/user_v2.yaml
+      OPENAPI_MOCK_SPECIFICATION_URL: '/etc/openapi/user_v2.yaml'
     ports:
       - 8080:8080
+    volumes:
+      - ./user_v2.yaml:/etc/openapi/user_v2.yaml
 
   backup:
     image: offen/docker-volume-backup:${TEST_VERSION:-canary}

test/dropbox/openapi-mock.yaml

@@ -1,25 +0,0 @@
-# OpenAPI specification options
-openapi:
-  specification_url: '/etc/openapi/user_v2.yaml'
-
-# web server options
-http:
-  cors_enabled: false
-  port: 8080
-  response_timeout: 1.0
-
-# application specific options
-application:
-  debug: false
-  log_format: tty
-  log_level: info
-
-# options to control generation process
-generation:
-  default_min_float: -1.073741823e+09
-  default_max_float: 1.073741823e+09
-  default_min_int: 0
-  default_max_int: 2147483647
-  null_probability: 0
-  suppress_errors: false
-  use_examples: 'if_present'