Added Arduino 1.6.9 to the continuous integration
Added Arduino 1.6.9 to the continuous integration

janelia-arduino/ArduinoJson,bblanchon/ArduinoJson,janelia-arduino/ArduinoJson,janelia-arduino/ArduinoJson,janelia-arduino/ArduinoJson,bblanchon/ArduinoJson,hemantsangwan/Arduino-Json,peterpolidoro/ArduinoJson,peterpolidoro/ArduinoJson,hemantsangwan/Arduino-Json,bblanchon/ArduinoJson,hemantsangwan/Arduino-Json,peterpolidoro/ArduinoJson,peterpolidoro/ArduinoJson