title: blank schema and validation
body: <p>If I have a blank JSON schema, such as</p>
  
  <pre><code>{}
  </code></pre>
  
  <p>and I try to validate the following data:</p>
  
  <pre><code>{
     "hello": "world",
  }
  </code></pre>
  
  <p>would validation be successful? (note the trailing comma).</p>
  
  <p>I tried using everit json schema validator in java,</p>
  
  <pre><code>JSONObject rawSchema = new JSONObject(new JSONTokener("{}"));
  
  Schema schema = SchemaLoader.load(rawSchema);
  
  schema.validate(new JSONObject("{\"hello\" : \"world\",}"));
  </code></pre>
  
  <p>and it seems to validate.</p>
  
  <p>Interestingly, some online validates this JSON </p>
  
  <p><a href="https://www.jsonschemavalidator.net/" rel="nofollow noreferrer">https://www.jsonschemavalidator.net/</a></p>
  
  <p>whereas others don't</p>
  
  <p><a href="https://json-schema-validator.herokuapp.com/" rel="nofollow noreferrer">https://json-schema-validator.herokuapp.com/</a></p>
  
  <p>The later uses a parser from Jackson before validating, perhaps that's the reason?</p>