QBatteryInfo Refactorization Step 2

-Remove EnergyUnit enum
-Change Win32 code to return mAh to conform to all other platforms
-Rename BatteryStatus to LevelState
-Add Health enum and property
-Rename a couple enum values

Change-Id: Ie359036f66f0b1f41d35cd8a574552f2a7b8bf00
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>