title: workflow warnings
body: <p>I'm trying to clean up the warnings being generated by some existing code.  I'm stuck on these 3... I really have no experience with workflows, so I have no idea what it's complaining about... any ideas?</p>
  
  <pre><code>warning WF1820: Activity 'StartWorkflowActivity' validation warning:
  Validation failed for parameter 'workflowName'. All parameters for
  the receive activity should have a valid activity binding or a value
  specified.
  
  warning WF1820: Activity 'ContinueWorkflowActivity' validation warning:
  Validation failed for parameter 'workflowContext'. All parameters for
  the receive activity should have a valid activity binding or a value
  specified.
  
  warning WF1821: Activity 'ContinueWorkflowActivity' validation warning:
  Validation failed for parameter '(ReturnValue)'. No valid activity bind
  or value found specified for return value.
  </code></pre>