hArduino-0.1: INSTALL

The usbArduino library can be installed simply by issuing cabal install
like this:

     cabal install sbv

The package depends on the usb library itself, which in turn relies on
the availability of the libusb package on your platform. See notes
at https://github.com/basvandijk/bindings-libusb for details on how
to get the latter.