uCON64 Code (SVN)

- Fixed overflow in unzip.c that caused unztell64() to fail for files larger
than 4 GB (inside zip archives).

- Removed a few redundant statements from ucon64_find_func().
- Refactored memcmp2() to reduce the number of branches.
- Mentioned wildcard in help for --hreplace.

- Change that may fix a possible issue on 32-bit big endian machines.

- Fixed memory leak in ucon64_replace().

- MinGW-w64 already has truncate(), but with size of type off32_t. Changed to a
proper fix.

- Visual Studio has no getopt.h. Decided to remove getopt2 functionality.

- Removed some libdiscmage getopt ugliness.
- Removed now redundant include directive.

- Removed unused src/libdiscmage/getopt.h.
+ Updated makefiles.
- Fixed compile errors in libdiscmage when compiling with MinGW-w64 and
-D_FILE_OFFSET_BITS=64.
- Removed prototype of no longer existing function in getopt2.c.

- The issue with MinGW-w64 and 64-bit Cygwin has disappeared with GCC 11.2.0.

- Defined Z_LARGE64 to enable zlib's *64 functions for Visual Studio.
- Removed stray whitespace at end of line.