Added I2C Support

Added I2C support. This should obviously be peer reviewed. I tested using an 8x8 Matrix LED display. Results are identical for Arduino and BBB. I also threw together a quick demo for the TMP102 temperature module, and results are identical for Arduino and BBB. 

I am not sure if it worth providing tests for the 3 i2c methods, since there is no pin manipulation to test.
Not sure what you thoughts on this might be.
I removed the console.log statements from the file.


On 12/04/2014 02:48 PM, Julian Duque wrote:
>
> In examples/i2cLedMatrix.js:
>
> > +    "10000001",
> > +    "10000001",
> > +    "01000010",
> > +    "00100100",
> > +    "00011000",
> > +    "00000000"
> > +  ];
> > +
> > +  var matrix = new five.Led.Matrix({
> > +    controller: "HT16K33",
> > +    isBicolor: true
> > +  });
> > +
> > +  matrix.clear();
> > +
> > +console.log("clear");
>
> can we remove console.log ?
>
> —
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> <https://github.com/julianduque/beaglebone-io/pull/13/files#r21330787>.
>