Add option to remove device frame / background on small device versions

[nsgundy]

From @Maffaxxx (see #59 (comment))
The small versions of all devices are still too big to be used as a navigation tool, mainly because of their frames (which are eyecandy but useless when you dont need to interact with the device itself).

If the whole device (whatever it is) is not resizable as one likes, at least insert an option to take the plastic frame out from view and leave just the map screen on in a corner of the HUD, just like vanilla GPS.

[Maffaxxx]

thanks nsgundy
i would like it possible at least for vehicles, which should be able to access a comfortabile GPS view while driving, while foot soldier should either stop or slow down to glance to their device and making any sense of what they are seeing -at least i need to stop and look at my phone GPS when im walking ;)