Updated Media Center "Time Travel" article for Windows Vista

Several months ago I updated my "Time Travel with Windows Media Center" article to be based on Windows Vista rather than on Windows XP.  It's now online!  If you're interested in writing background add-ins for Media Center, check it out at https://msdn2.microsoft.com/en-us/library/bb643809.aspx.

Thanks to Charlie Owen for his help in getting it posted.