NoReplyAll Add-In 2.4.2

A new version of the add-in is now available - head to https://research.microsoft.com/en-us/downloads/60860f41-88ab-4bb4-8104-765feca9cfed/default.aspx to get hold of it.

This is to fix a problem with misidentification of HTML embedded images as attachments, confusing the missing attachment detector.