BME280 implementation

[Razican]

OpenStratos 1.1 will have the BME280 sensor that will give readings for humidity, temperature and pressure during the ascent and descent. Nevertheless, we need to implement it in our project so that we can use it. The reference implementation will be this provided by Adafruit for Arduino: https://github.com/adafruit/Adafruit_BME280_Library

Since we use WiringPi, only parts that can be overriden/improved by the C++14 standard will be changed. It provides a pretty good API compatible with OpenStratos standards almost completely.