Arduino path

If Arduino can not be found at default path, then ARDUINO_HOME environment variable should be set.

on Ubuntu (https://help.ubuntu.com/community/EnvironmentVariables): in ~/.profile:

ARDUINO_HOME=~/opt/arduino
export ARDUINO_HOME

temporary changes:

$ env ARDUINO_HOME=~/opt/arduino-0022 python -m confduino.version
0022

$ env ARDUINO_HOME=~/opt/arduino-1.0 python -m confduino.version
1.0

Default path:

• Mac: /Applications/Arduino.app/Contents/Resources/Java
• Linux: /usr/share/arduino/