Murf1
Android Enthusiast
It appears the MM "Doze" feature was excluded from the Boost version of Marshmallow. However, I found this app via the "Drippler" app that does the same thing and you don't have to be rooted. Actually, it doesn't wait 30 minutes like the real Doze does to do it's thing.
https://play.google.com/store/apps/details?id=com.yirgalab.dzzz&hl=en
https://play.google.com/store/apps/details?id=com.yirgalab.dzzz&hl=en