MS Outlook add-in for email processing

I am building an email processing tool for corporate users. It consists out of two main parts: email processing engine and Outlook add-in interfacing user's MS exchange account. This project target is the Outlook add-in part that should add some UI elements to the Outlook (buttons), update processing engine up on new email received and modify some email parameters per engine's request. The add-in should be work fine with corporate Exchange accounts. The Outlook add-in code should be written in JavaScript/HTML as described here: [login to view URL]