* develop:
Typo fix
Version bump to 2.9.4
Show "udev" warning only for the Linux OS while upload firmware
Version bump to 2.9.3
Notify Linux user to install PlatformIO udev rules
Add new article
Add support for Arduboy
Remove unused imports
Refactor firmware uploading to the embedded boards with SAM-BA bootloader
Fix firmware uploading to the embedded boards with SAM-BA bootloader
Add explanation about waiting for the new serial port
Hook when new serial port is the same in boot mode
Revert back some code linked with uploading to Leonardo/Due
# Conflicts:
# platformio/__init__.py
# platformio/boards/misc.json
# platformio/builder/scripts/atmelavr.py
# platformio/builder/scripts/atmelsam.py
# platformio/builder/tools/pioupload.py