OpenSystemsDevelopment / qpdf

For wildcard expansion to work properly with the msvc binary, it is
necessary to link with setargv.obj or wsetargv.obj, depending on
whether wmain is in use.

Thanks to Zdenek Dohnal <zdohnal@redhat.com> for contributing the code
used for the gnutls crypto provider.

Based on sizeof(size_t). Assumes 64 if not 32.

Rather than checking consistency of libqpdf.map, generate it.

Also separate C and C++ warning flags.

Make --enable-werror work properly on msvc, handle extra warnings
flags for msvc in configure.ac instead of hardcoding into
make/msvc.mk, separate warnings flags into WFLAGS in autoconf.mk to
avoid duplication and to make it easier to override.

LARGE_FILE_TEST_PATH -> QPDF_LARGE_FILE_TEST_PATH
SKIP_TEST_COMPARE_IMAGES -> QPDF_SKIP_TEST_COMPARE_IMAGES

Update the build to support new external-libs layout, and autoconf
options to specify windows word size.  Split make_windows_releases
into multiple scripts.

For ELF systems, turn on versioned symbols by default, and add a
configure option to enable or disable them.

git-svn-id: svn+q:///qpdf/trunk@870 71b93d88-0707-0410-a8cf-f5a4172ac649

git-svn-id: svn+q:///qpdf/trunk@764 71b93d88-0707-0410-a8cf-f5a4172ac649

git-svn-id: svn+q:///qpdf/trunk@760 71b93d88-0707-0410-a8cf-f5a4172ac649

git-svn-id: svn+q:///qpdf/trunk@599 71b93d88-0707-0410-a8cf-f5a4172ac649