an esp8266 mqtt wrapper for chiang mai maker club

• https://github.com/bblanchon/ArduinoJson
• http://github.com/Imroy/pubsubclient

To allow building an application using this library, you need to "git clone" the project from within your Arduino library directory.
On Windows 10, it should be under:
C:\Users\<your username>\Documents\Arduino\libraries\
Now you should be able to compile the examples.

This library was initially intented to periodically communicate sensor data.

Provided examples use 3 files:

• main arduino file : define your connection details and the usual setup() loop() Arduino stuffs.
• init_mqtt.h : specify some protocol settings, subscriptions and implement you own connection event handlers
• _publish.h : implementation of your publish hooks (periodic procedures relative to outgoing data: sensor read, data formatting...) Data is sent to a default topic.
• _receive.h : implemention of your subscribe hooks (message handlers)

@DoNcK also added the option to send data spontaneously, not periodically, on a specified topic, using:
void sync_advpub(String prefix, String topic, String payload, bool retain); (The prefix and topic arguments are not yet fully functional)

Warning:
It not asynchronous, so it will only return afer sending the payload. It can take some time on very loaded networks and prevent your main loop() from running smoothly.