title: JIRA pluggin Development - Show alert/notification
body: <p>I am currently developing a JIRA plugin of type Workflow post function. </p>
  
  <p>This means I dont have a use for the vm file (velocity template).</p>
  
  <p>I have a  java class which extends AbstractJiraFunctionProvider. it basically calls a web service (asynchronously) using SOAP to update a remote system on the status of the JIRA issue. </p>
  
  <p>I have got it all working and configured to be triggered when certain JIRA status transitions are done. 
  What I am trying to do is to show a message to notify the user if the web service has been called successfully or not. 
  How do I show a popup message with some text. 
  I tried <code>JOptionPane.showMessageDialog(null,"Text","Text 2")</code> to my Plugin class
  But this doesn't seem to do anything from the plugin java class which extends AbstractJiraFunctionProvider.
  Any thoughts or ideas for me to try?</p>