Code Cleanup

Let's submodule the Adafruit library and implement the missing function calls. Doing so should elminate any copy-paste from external repos and keep up with any bugfixes on their end.

To get there, we need to:

## Implement a blank Adafruit_I2CDevice
This is included as `#include `, and we'll need to stub out the read and write functions.

## Implement Adafruit_SPIDevice and read/write functions
````cpp
class Adafruit_SPIDevice
{
// constructor
Adafruit_SPIDevice(cspin, 1000000, SPI_BITORDER_MSBFIRST,
SPI_MODE0, theSPI)
}
````

## Implement Arduino.h
This should be another submodule from AIND. Ask @Poofjunior for the location of this.

## File Organization
Let's submodule https://github.com/adafruit/Adafruit_BME680/tree/master into the **lib** folder.