Created by: Lekensteyn
This applies to K800 but it seems also to apply to M510. The numbers are based on the HID++ 2.0 spec that state the following for GetBatteryCapability:
If number of levels < 10 or if mileage is disabled then report are
mapped to 4 levels this way.
0%->10% critical
11%->30% low
31%->80% good
81%->100% full
i.e. to report battery low, FW send 25%, to report battery good, FW send 50%.
This patch likely closes #5 (closed).