Attempt at a MOF variant of hid2hci.ps1

This Managed Object Format (MOF) file should be the better alternative to
hid2hci.ps1 as it registers a permanent event filter and consumer with WMI.
Run through "mofcomp" to try out.

But it seems that Windows 8.1 by default doesn't see the whole WMI event
system after bootup: nothing happens if I plug in the USB Bluetooth adapter
at all. At some point in time things would suddenly work, but I couldn't
even determine WHAT led to that effect.