Fixes for battery levels, OS/device names, and allowing UWP to install via StorageFiles

Devices without batteries (IoT, some desktops, Xbox) will no longer report "NaN" for their battery level, but instead show at 100%.
A new InstallApplicationAsync function for UWP has been added that supports use of StorageFile, making it easier for UWPs to find and install appx via the File Explorer.
Desktop will now display the device type (e.g. type of laptop) rather than "Unknown".