title: ConfigurationBuilder not working in azure function
body: <p>I'm using azure functions template project in VS2017 and choosing version <strong>2 (beta)</strong>. I published it unchanged and it worked. </p>
  
  <p>I added nuget package <strong>Microsoft.Extensions.Configuration</strong> and wrote a single statement to initialize an instance of <strong>ConfigurationBuilder</strong></p>
  
  <pre><code>public static class Function1
  {
      [FunctionName("Function1")]
      public static IActionResult Run([HttpTrigger(AuthorizationLevel.Anonymous, "get", "post", Route = null)]HttpRequest req, TraceWriter log)
      {
          var cb = new ConfigurationBuilder();// &lt;&lt;&lt;&lt;&lt; added line
          log.Info("C# HTTP trigger function processed a request.");
  
          string name = req.Query["name"];
  
          string requestBody = new StreamReader(req.Body).ReadToEnd();
          dynamic data = JsonConvert.DeserializeObject(requestBody);
          name = name ?? data?.name;
  
          return name != null
              ? (ActionResult)new OkObjectResult($"Hello, {name}")
              : new BadRequestObjectResult("Please pass a name on the query string or in the request body");
      }
  }
  </code></pre>
  
  <p>With this code the function crashes with 500 - internal server error and I cannot find any reason. </p>
  
  <p>Am I missing something? How do I access configuration information in Azure functions (v2.0)</p>
  
  <p>Edit:
  Executing in Compute emulator throws 
  <em>System.Private.CoreLib: Exception while executing function: Function1. Aweton.Labs.AzureFunc1: Could not load file or assembly 'Microsoft.Extensions.Configuration, Version=2.1.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'. The system cannot find the file specified. System.Private.CoreLib: Could not load the specified file.</em></p>