uCON64 Code (SVN)

- Fixed resource leak introduced with previous change.
- Corrected explanation.

- Found the official homepage of MinGW by chance. Updated the link in the FAQ
and fixed the warnings produced by the current version of MinGW (ftime() and
struct timeb are removed from the latest POSIX standard (POSIX.1-20017) --
switched to the Windows-specific _ftime() and struct _timeb).
- Re-added the work-around for linking libcd64 on Windows with the 64-bit
versions of GCC and now also Clang.
- Added extra error check to Windows implementation of truncate().
- Fixed a bug in unregister_func() when passing NULL as argument.
- Enabled calls to drop_privileges_temp(), drop_privileges() and
regain_privileges() on macOS, just to do the same as on the other UNIX OSes.
- Fixed warning on UNIX OSes other than GNU/Linux about unused exec() in f2a.c.

- Fixed previous fix (files 0 bytes in size caused trouble, for example for
--padn).
- Made displaying bits of a byte slightly more elegant.

- Fixed -j which I broke horribly in 2.2.2. Painful, but this is what can
happen if functionality is not tested nor used.

- The header of libusb-0.1 that comes with Cygwin 32-bit is usb.h.

- Increased the version to 2.2.3 (WIP).

- Direct to the right place for OpenBSD binaries.

- Tagging uCON64 version 2.2.2 as it is released.

- Branching uCON64 version 2.2.2 as it is released.

- Released uCON64 2.2.2.