We never tested compiling without it.  Just kill it.  We always build
our own shaper.

Instead of passing a CFLAG/CXXFLAG to define HB_EXTERN, define it
directly in src/hb.hh as __declspec(dllexport) extern when we are
building HarfBuzz as DLLs on Visual Studio.  Define HB_INTERNAL
as nothing without defining HB_NO_VISIBILITY when building HarfBuzz as
DLLs to avoid linker errors on Visual Studio builds.

Also "install" harfbuzz-subset.dll into $(PREFIX)\bin as the
hb-subset utility will depend on that DLL at runtime, when HarfBuzz is
built as DLLs.  Since it consists of private APIs that are subject to
change, we do not install its headers nor .lib file.

When building with the auto tools, the manually mantained
harfbuzz-config.cmake is installed. When building with cmake, we can use
cmake to generate the correct config files for us and install them.

let python's parse command-line args as usual

To avoid need of CMP0063 which is not available on older CMake versions

Later to be expanded to a more general tool but for now it only supports CBDT, SVG and CBDT.

...on static builds.

But keep use of cmake idiomatic way of making inlines hidden

This covers all built libraries now and both static and shared builds.

This change makes sure that non-MSVC builds using CMake properly hide
non-exported functions.

Put in the utility program that was missed in installation by replacing
the one that was duplicated.

The list of source files to pass to g-ir-scanner is becoming too
long for Windows, as Windows imposes a 8192-character limit for command
lines, so we need to first transform that list into a listings file, and
then use the --filelist option for g-ir-scanner to build the
introspection files.

Not all the compilers that HarfBuzz is buildable on supports round() and
has the header stdbool.h, so we check for them and define HAVE_ROUND and
HAVE_STDBOOL_H repsectively in our CFLAGS so that we include them only
when they are found, or use fallback implementations when necessary.

Also include FindPythonInterp earlier as we need PYTHON_EXECUTABLE to be
set for running the tests.

Also, call c++filt on their results.

Also build and fix and check harfbuzz-gobject.def

Also changes harfbuzz-gobject to distribute generated enum sources.