* add sample for si7021 temperature read over i2c

* add Si7021 device class

* remove ReadTempFromSi7021.cs

* add device sample for Si7021 and humidity read command

* remove reference to README in Si7021 csproj file

* Added device binding template readme

* Folder name was clipped

* Heck wording

* Add BMP280 device binding

* Fixing according to comments
Renaming, binary format, readme, solution file.

* the missed sample file update

* No more vars
Renaming and moving around for better structure
Made read methods private

* Changed to BinaryPrimitives
Simplified ByteToSampling

* coefficients/calibrationdata is now short/ushort instead of int/uint

* even better read method naming

* Moved reading calibrationdata to calibrationdata class

* Better Register enum
Fixing read24bits

* Added initial binding template

* Updated links

* Fixed link

* Add initial Mcp23xxx binding

* Added Fritzing files with I2C connection

* Removed conneciton link from I2C circuit

* Added summary comments for Bank

* Removed controller code based on feedback

Various code cleaning and functionality improvements

* Adding Licensing headers to our .cs files

* Moving files to the System.Device.Gpio namespace