This is only a cosmetic change, to make the IrDA device address on
Windows consistent with the address Linux. There is no functional
difference because the address is always serialized and deserialized
internally, and applications shouldn't care about the actual number.
Anyway, the difference in endianness is easy to notice because the
Uwatec Smart family of devices use the serial number as the IrDA device
address. On Linux, the address was identical to the serial number, while
on Windows the byte order was reversed.
Apparantly, the windows wingdi.h header file already defines the
ERROR macro. By defining the NOGDI macro before including the
windows.h header file, we can prevent the wingdi.h file from being
included and thus avoid the warning. We don't need that header for
anything anyway.
Because the libusb header file includes the windows.h file
explicitly, it needs the same fix.
The Windows WSAStartup() and WSACleanup() functions are now called
automatically when opening and closing IrDA sockets. This causes no
problems because these functions are reference counted and can be called
multiple times.
In practice nothing changes because the Uwatec Smart backend already
called these functions for every connection.
The public header files are moved to a new subdirectory, to separate
the definition of the public interface from the actual implementation.
Using an identical directory layout as the final installation has the
advantage that the example code can be build outside the project tree
without any modifications to the #include statements.
