title: adding Outlook 2013 mailitem contextmenu. VS 2012 C#
body: <p>Hi i want to add a new button to outlook 2013 mailitem contextmenu. 
  I use VS 2012 C#.</p>
  
  <p>I seached internet but cant find a way to do this, im upgrading an Outlook 2010 addin which modified the contextmenu.</p>