All players have some sort of keyboard control, Libreflix should
have this too! This patch makes the playback controllable by
the left and right arrow keys and the volume controllable by
the up and down keys.
The volumeChange function was rewritten to utilize the changevolumeDelta so we don't have code duplication!
So that's it, I hope that the PR gets accepted, but if anything
needs to be changed, please let me know!
[Let's change the world, one smile at time ;D]
You're awesome, Matt! Thank you for your PR.