title: Angular 7 http.post JSON number sent as string
body: <p>I have an Angular class defined with a property (timeout) of type 'number':</p>
  
  <pre><code>export class EngineSpec {
      name: string;
      base_url: string;
      version: string;
      timeout: number;
      tls: boolean = false;
      user_agent: string;
    }
  </code></pre>
  
  <p>However, when I http.post an instance of this class, the property is sent as a string:</p>
  
  <pre><code>{"tls":false,
    "name":"local-vm",
    "base_url":"http://localhost:2367",
    "version":"1.3",
    "timeout":"60"
  }
  </code></pre>
  
  <p>Any ideas why a number is getting sent as a JSON string?</p>