title: StoredProfileAWSCredentials complains it cannot find the profile in a Web application
body: <p>I am seeing the following error being returned when I run the <code>StoredProfileAWSCredentials</code> default constructor from within a web application:</p>
  
  <pre><code>System.AggregateException: One or more errors occurred. ---&gt; System.ArgumentException: Path cannot be the empty string or all whitespace.
  Parameter name: path
     at System.IO.Directory.GetParent(String path)
     at Amazon.Runtime.StoredProfileAWSCredentials.DetermineCredentialsFilePath(String profilesLocation) in d:\Jenkins\jobs\build-sdkandtools-release\workspace\sdk\src\AWSSDK_DotNet35\Amazon.Runtime\AWSCredentials.cs:line 354
     at Amazon.Runtime.StoredProfileAWSCredentials..ctor(String profileName, String profilesLocation) in d:\Jenkins\jobs\build-sdkandtools-release\workspace\sdk\src\AWSSDK_DotNet35\Amazon.Runtime\AWSCredentials.cs:line 300
     at Amazon.Runtime.StoredProfileAWSCredentials..ctor(String profileName) in d:\Jenkins\jobs\build-sdkandtools-release\workspace\sdk\src\AWSSDK_DotNet35\Amazon.Runtime\AWSCredentials.cs:line 270
     at Amazon.Runtime.StoredProfileAWSCredentials..ctor() in d:\Jenkins\jobs\build-sdkandtools-release\workspace\sdk\src\AWSSDK_DotNet35\Amazon.Runtime\AWSCredentials.cs:line 260
  </code></pre>
  
  <p>I am calling this method with no parameters.  I have a "default" profile defined which has worked when it has been used.   The web application is running under IIS 6.1 in an application pool which uses my credentials (since the AWS credentials were obtained under my login).</p>
  
  <p>I have tried using the two-parameter constructor with the name "default" and the local disk path to the <code>RegisteredAccounts.json</code> file (which was generated for me by the AWS Toolkit extension for VS 2013).</p>
  
  <p>What is happening here and how do I fix it?  </p>