Functionality for remaining percentage (linux)

[meepoSenpai]

This should add functionality to also get the remaining battery percentages of all batteries on linux

[Kentzo]

@meepoSenpai We should add implementation for get_remaining_percentage for all other platforms. Even if the implementation simply raises NotImplementedError.

[meepoSenpai]

It should suffice to raise a NotImplementedError in the Superclass, correct?

[Kentzo]

Since it's an @abstractmethod it has to be implemented.

[Kentzo]

get_remaining_percentage must be implemented for Windows or Darwin before this can be merged.

[kootenpv]

I would say "Power" as a package is not complete until a few more things are being taken care of, such as get_remaining_percentage and get_time_remaining (which just works in an os-independent way).

[Kentzo]

@kootenpv What is the difference between get_time_remaining_estimate and get_time_remaining?