I know this is an old thread. And I understand that Ti Backup used to work for detaching an app from Play Store. But I also understand that this works no longer. For those who are interested, I have created an app that does a pretty good job of this. It is called Hide Updates In Play Store. There is a video showing the app at work. It does, however, require root. Yet another good reason to have a rooted device! Thanks
(search Play Store for com.whitedavidp.hideupdatesinplaystore)