Implement a dynamic scheduler daemon

systemd76-scheduler is a nice daemon to dynamically re-tune CFS based on power availability (on battery vs plugged into wall), running app (boost priority of the app receiving focus), and hard-coding default priorities to different executables (so we can, for instance, automatically de-prioritize compilers and other such batch background tasks)

I'm not sure I agree with that last point, but the rest seems useful. Here's issues with the last point:

• The user might actually want their compilers to have somewhat high or at least normal priority
• Priority for known background processes should be configured through systemd