Moving device and deviceUsage to same place

[Peyman-N]

It seems that device and deviceUsage are in different places. One is in products and other one is in research. So I believe they should moved to the same location. I would prefer research but I am not sure about it. As soon as you decide I would do the pull request.

[lzehl]

From where they are used the current sorting actually makes sense. The device itself is a static product which can be bought or distributed, while it's usage/application belongs to research.

I'd like to hear more opinions on this before we make a decision.