Feature request: acceleration output in Earth coordinate system

[artur-iluk]

In blackbox_decode the acceleration out in done in controller coordinate system. It would be useful to have possibility to output accelerations in the Earth coordinate system, with gravity removed (az-1g).
It is done in what way in blackbox_render, so it should be quite simply.
All functions already exists in the code blackbox_render.
It is just a matter of output these values to .csv file by blackbox_decode.

Proposed command line switch for blackbox_decode:
--acceleration-csys acceleration output coordinate system (controller|Earth), default is controller

[mikeller]

Sounds reasonable - feel free to open a pull request to implement this change.

[artur-iluk]

I know that change is simple, but I'm just a user of software and don't know how to modify the soft. I'm not familiar with github as well, so I'm not a person to make a pull request (requires some code?). It was just proposal of me.

I hope someone more proficient will have some time to modify the code make a pull request.