Logging: add code to download log files while running

This is mirrored from the picoC code and allows downloading
from log files in 32 byte chunks.

Conflicts:
	flight/Modules/Logging/logging.c
	shared/uavobjectdefinition/loggingstats.xml
GCS/Logging: code to download logs from running FC

This adds a menu option that will iterate through a log
file and download it from the flight controller to a
file.