Duplicated include; improved shutdown.c; store data even without switch

[Gabrielerusso]

commands.c:

• Delete duplicated include "mc_interface.h"

shutdown.c / shutdown.h / main.c:

• Reducing possibility to write backup data frequently, now requires minimum distance to be traveled before it enables storing, common condition if push to start is enabled with a low shutdown time, say 10s, or in any other condition where user turn on/off ESC a lot of times. Saves chip life at the cost of not having updated data during very short trips.
• Data is stored even when using "always on", basing storage condition on the inactivity time, this allower user that shutdown esc from the power source to keep data anyway or in case of a power loss.
• Introducing possibility to store data without a power-switch by using a combination of trip distance and inactivity timer, it estimates when the scooter it's stopped for a long period after a trip, now user to save trip data just need to leave the scooter still an X amount of time to make sure all data is stored. It can be deactivated by using "always off" in app setting Shutdown Mode.

Compiled almost all version without issues, tested on my custom esc with different combinations (with power switch, without power switch) and it seems to work well.

[Gabrielerusso]

Tested in those weeks with 4 escs and different configuration, 2 with power switch and 2 without, now i was able to save data, like the odometer without problems even in the version without the power switch.

[1zun4]

Please merge this. This also solves my https://github.com/vedderb/bldc/issues/638 problem, as the only reason I need it is to store odometer data without software shutdown.