Feature idea summary

Cgroups plugin supports only proportional and max Block IO policies. We should support BFQ scheduler as well. Disk stats for the scheduler are in blkio.bfq.io_service_bytes and blkio.bfq.io_serviced files.

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What is the feature ?

I'm trying out this library for the first time and I'm seeing several places where some shorthand functions would have been really pleasant:

1. Shorthand functions for Pos: Pos::top_right, Pos::bottom_right, Pos::bottom_center etc..
2. Short way to set colors for components. My plots are supposed to be white-on-black, which requires a lot of boilerplate on lots o