Clean up FLTKConfigVersion.cmake too and actually install cleaned
.cmake files.

Fix a typo and add a conditional alternative symbol.

* debian/libfltk1.4.symbols: Exclude from m68k one template symbol that
  came along for the ride everywhere else.
* debian/libfltk1.4.symbols.32-bit: Correct multiple negation syntax,
  unbreaking i386 builds.

Some libfltk1.4 symbols vary slightly on 32-bit non-i386 architectures.

It's std::__va_list, not just __va_list.

There are no compressed manpages to indicate the uncompressed ones to
ignore, so just ignore them all.

See #1080497.

With ports in the picture, there are five(!) possibilities, each of
which can occur in both 32- and 64-bit flavors.  Map architectures
to types on the basis of other packages' pkgkde-symbols-helper runs.

Note that it gets a forked source package, with fltk1.3 remaining
present and getting (a little) more attention.

Upstream version 1.4.2

Upstream version 1.4.1

* debian/control: fltk1.4-games mentions flpuzzle, whose needs are
  relegated to Recommends.
* debian/rules: Install glpuzzle (a Klotski implementation), as
  flpuzzle, relegating anything only it needs to Recommends.
  (Installation suggested by upstream developer Albrecht Schlosser.)

Affects debian/libfltk1.4.symbols(.*-bit-only) and debian/rules.

* debian/*.symbols: Update accordingly; under CMake,
  libdecor-cairo-blur.c is (harmlessly, AFAICT) out of the picture in
  the presence of external libdecor.
* debian/fix-fltk-config: New, because the traditional one-liner doesn't
  cut it with the CMake build system.
* debian/fltk1.4-doc.docs: Drop in favor of CMake PDF installation.
* debian/fltk1.4-doc.examples: Copy relevant portions of (obj-*/)test.
* debian/fltk1.4-doc.install: Let CMake install HTML.
* debian/libfltk1.4-compat-headers.install: Don't expect
  fl_file_chooser.h under CMake.
* debian/libfltk1.4-{compat-headers,dev}.links: Make explicit
  fl_file_chooser.{h,H} symlinks.
* debian/libfltk1.4-dev.install: Retain our ersatz CMakeCache.txt even
  under CMake; the full version is architecture-dependent.
* debian/rules:
  - Drop anything specific to the traditional build system.
  - Explicitly define CP936 and -fvisibility-inlines-hidden for lack
    of corresponding CMake build system options.
  - Set DEB_C(XX)FLAGS_MAINT_APPEND from XCFLAGS.
  - Change cmake_out to obj-$(DEB_HOST_GNU_TYPE).
  - Set LD_LIBRARY_PATH for the sake of dynamically linked local fluid.
  - Explicitly suppress dh_autoreconf(_clean) and
    dh_update_autotools_config.
  - Ensure fix-fltk-config's executability too.
  - Set FLTK_INSTALL_{HTML,PDF}_DOCS, CMAKE_SKIP_RPATH, and (for now)
    CMAKE_HAVE_THREADS_LIBRARY; however, set FLTK_INSTALL_* only when
    building architecture-independent packages.
  - Invoke CMake's docs target for documentation.
  - Copy games from under $(cmake_out).
  - Postprocess fltk-config with fix-fltk-config.
  - Clean up duplicate uncompressed man pages.
* documentation/CMakeLists.txt:
  - Set timestamp values, including a new TODAY, via CMake's
    SOURCE_DATE_EPOCH-honoring builtin.
  - Adjust installation destinations.
* fltk-config.in: Drop added sed calls in favor of fix-fltk-config.
* {fltk-options,fluid}/CMakeLists.txt: Link to shared FLTK libraries.

* debian/libfltk*1.4.install: Accommodate paths that include patchlevels.
* debian/libfltk1.4-dev.install: Move CMake support files from
  /usr/lib/fltk to /usr/share/fltk, where FLTK's CMake build system
  puts them.  They're already necessarily architecture-independent to
  allow for multiarch coinstallability.
* debian/rules:
  - Move XCFLAGS up.
  - Supply CMakeTmp via a new cmake_out macro.
  - Install CMake support files to /usr/share/fltk rather than
    /usr/lib/fltk.
* documentation/{Makefile,src/fltk-title.tex.in}: Uniformly use @...@
  for substitutions for CMake compatibility; specifically, change \today
  to @TODAY@.
* documentation/make_pdf: Consult SOURCE_DATE_EPOCH directly.

* debian/control: Add a new fltk-options binary package, which
  libfltk1.4 suggests. (Its contents are small, but folding it in
  would break multiarch support.)
* debian/fltk-options.*: Populate new fltk-options package.
* debian/rules: Build and install fltk-options.
* fltk-options/Makefile: Install modern MIME XML metadata rather than
  a legacy mimelnk .desktop file that doesn't even exist.

* debian/control: Add build dependencies needed for the new Wayland
  backend: libdbus-1-dev, libdecor-0-dev (>= 0.2.0) | libgtk-3-dev,
  libegl-dev, libglew-dev, libpango1.0-dev, libwayland-dev,
  libxkb-common-dev, and wayland-protocols.
* debian/libfltk(-gl)1.4.symbols: Update appropriately.  Some symbols
  associated with the Xlib and PS(!) backends are gone, but that's not
  a concern at this stage.
* debian/rules: Revert passing --disable-wayland to dh_auto_configure
  in favor of belatedly covering the new libdecor/build subtree in
  override_dh_auto_build-arch so the Wayland backend can build.

Specifically, enable FLTK_OPTION_CAIRO_EXT, FLTK_BUILD_SHARED_LIBS,
and FLTK_INSTALL_LINKS.

Avoid warnings now that the latter contains the C-only
-Werror=implicit-function-declaration.

Leave minimum versions at 0, even for symbols absent in the previously
packaged snapshot, which never got beyond Salsa.  Anything subsequent
actual releases introduce will be another matter.

* debian/FLTK-Targets-none-tail.cmake: Prefix fluid with fltk::.
* debian/fix-fltk-targets:
  - Account for modern fltk::* target names (including for executables)
    and for suffix changes (-shared/-static rather than _SHARED/_STATIC).
  - Clean up stray new references to (system) library directories.
  - Update one more explicit 1.3 reference, likely previously missed
    due to the lack of a preceding "fltk".
* debian/rules: When sanity-checking the postprocessed
  FLTK-Targets-none,cmake, look for [_cmake_import_]check_targets
  rather than add_*, no longer present in raw output either.