Use a bold header and colorize the space suffixes in iostat
by order of magnitude like this:
- K is green
- M is yellow
- G is red
- T is lightblue
- P is magenta
- E is cyan
- 0 space is colored gray
Signed-off-by: Ethan Coe-Renner <coerenner1@llnl.gov>
Signed-off-by: Tino Reichardt <milky-zfs@mcmilk.de>
Closes: #14459