Publish refactoring (#298)

* factoring of the publishing function
* integration of json publishing to MQTT
* receiving and transcode json messages from mqtt
* replace the TRACE runtime condition by a buildtime one so as to decrease program size
* remove retainFlag parameter not necessary for the moment
* Increase the scope of tests for arduino mega and esp32
* Update arduinojson library to 5.13.3
* add macros to choose between simple or json publishing or both
* differentiate build test for ATmega2560
* correct wrong sprintf definition
* change IDE version for continuous integration
* let default warning level in arduino ide
* correct pins for ESP32
* reorganize user_config

.travis.yml

@@ -10,9 +10,9 @@ before_install:
   - "/sbin/start-stop-daemon --start --quiet --pidfile /tmp/custom_xvfb_1.pid --make-pidfile --background --exec /usr/bin/Xvfb -- :1 -ac -screen 0 1280x1024x16"
   - sleep 3
   - export DISPLAY=:1.0
-  - wget http://downloads.arduino.cc/arduino-1.8.5-linux64.tar.xz
-  - tar xf arduino-1.8.5-linux64.tar.xz
-  - sudo mv arduino-1.8.5 /usr/local/share/arduino
+  - wget http://downloads.arduino.cc/arduino-1.8.6-linux64.tar.xz
+  - tar xf arduino-1.8.6-linux64.tar.xz
+  - sudo mv arduino-1.8.6 /usr/local/share/arduino
   - sudo ln -s /usr/local/share/arduino/arduino /usr/local/bin/arduino
 install:
   - ln -s $PWD /usr/local/share/arduino/OpenMQTTGateway
@@ -31,7 +31,6 @@ install:
   - arduino --pref "boardsmanager.additional.urls=http://arduino.esp8266.com/stable/package_esp8266com_index.json" --save-prefs
   - arduino --install-boards esp8266:esp8266
   - arduino --board $BD --save-prefs
-  - arduino --pref "compiler.warning_level=all" --save-prefs
 script:
   - arduino --verify --board $BD $PWD/OpenMQTTGateway.ino
 notifications: