kodev: improve run --simulate …

[benoit-pierre]

Simulate a black & white screen for devices that don't support colors.

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This change is 

[benoit-pierre]

Only some of the kindles, but this should probably be extended to all other devices, except hidpi and maybe kobo-clara?

List of supported simulated devices:

• legacy-paperwhite
• kobo-forma
• kobo-aura-one
• kobo-clara
• kindle-paperwhite
• kobo-h2o
• hidpi

[Frenzie]

Hm, perhaps this is a bit like that xkcd with the emacs spacebar heating feature (with the distinction that to some extent I purposefully wrote it to heat with spacebar) but I always use kobo-aura-one for the size and DPI (i.e, it's effectively my default).

I do color vs b&w with the environment variable or the menu toggle. I had never intended to try to capture such secondary characteristics there and I would need a different way to sanely (as in without added baggage like b&w or flash) reach my various realistic size/DPI presets.

(The Clara in question is ye olde, definitely not color.)