UnicodeDecodeError

[imheresamir]

Hello,

During my evaluation of this library, I believe I came across a bug that was introduced in 913ac51 in BBIO_base.response():

the return value was changed from data to data.decode()
which will raise a UnicodeDecodeError when reading or writing values greater than 0x7F.

I was testing the SPI bus using Python 3.5.

I apologize for not submitting a pull request but I believe this change in response() behavior affects the other subclasses of BBIO wherever response() is called, and have decided to go with pyBusPirate instead.

Samir