Arduino integration

We're planning to release an Arduino library for integration with OpenIoT and possibly - with IoTCafe up to some extent.

This is part of the Apps rework, planned for IoT.Cafe v2.0, however it requires more human resource than we can spend right now, so it will probably come along with v2.0 or perhaps a bit sooner

The library will allow Arduino users to effortlessly connect their boards with the IoTCafe apps and use the apps to read values from their Arduinos and control them, similar to an IoT.Cafe device