Add support for Dell XPS 13

[RasmusLindroth]

Hi!

As you have stated in the readme it doesn't support all types of laptop batteries. To support for Dell XPS 13, and other laptops from Dell I suppose, you would need these changes.

RasmusLindroth@a534134

I could help you implement it but I'm not sure what the best way is. One alternative would be to would have to state your model in the configuration file, but I think the more cleaner solution would be to check if either POWER_SUPPLY_ENERGY_FULL or POWER_SUPPLY_CHARGE_FULL is set in /sys/class/power_supply/BAT0/subsystem/...

By the way, thank you for your software :)

[denbeigh2000]

Hey, thanks for the report!

I think the best way to approach this is to (finally!) remove my sketchy uevent parsing, likely in favour of an external library like https://github.com/distatus/battery.

I should have some time to tend to this in a week or two, when there is less real life in the way :-)

Thanks for using my software!