The sense of this `output` flag has been inverted (always?) for a long time.
1. I have the option "Delay sending until docked" showing as *off* in the UI.
2. My config.output value is `100000000001`.
3. The value of this flag is `4096`, which means 12th bit (starting from 1, not
zero).
4. So I have the bit set, but the option visibly off.
So, rename this both to be more pertinent to its use *and* to be correct as to
what `True` for it means.
1. You end up either inverting the sense of a `coverage_conditional_plugin`
pragma's name (versus what it actually tests), *or* where you put it in
the code.
2. As the pragmas are only defined in once, in one place, it's better to
invert the sense there, rather than in *every single use case*.
Then technically any 'other' branch isn't guaranteed to
* Define `darwin` and `linux` *and* "platform known" pragmas.
* Use per-platform pragmas in `config/__init__.py` selection of implementation.
* Attempt, and fail, to use pragma in `config/darwin.py` to ignore it on
other platforms.
Does what it says on the tin. Moves config implementations out to
individual files, guards those around platforms to make stuff more
reasonably split out.
