Implement channels mapping calibration.
Store mapping in parameters.
Get rid of `controls` array and store control inputs in `controlRoll`, `controlPitch`, ... variables.
Move `channels` variable to rc.ino, channels are not involved when controled using mavlink.
'Neutral' values are renamed to 'zero' - more precise naming.
`controlsTime` is renamed to `controlTime`.
Use unsigned values for channels.
Make channel values in simulation more alike to real world: unsigned values in range [1000, 2000].
Send RC_CHANNELS_RAW instead of RC_CHANNELS_SCALED via mavlink
Don't send channels data via mavlink if rc is not used
* Create book structure.
* Add workflow for linting the markdown using markdownlint.
* Add workflow for building the book with mdBook and deploying to the website.
* Restyle mdBook and support GitHub-style alerts.
* Add images zooming.
* Add index, firmware structure and gyroscope articles.
