Bug 54948 - Undefined symbols: "operator delete(void*)" "operator
new(unsigned long)" "___cxa_pure_virtual"

Eventually this will become part of a yet-to-be-written hb-ot cmdline
tool.

API additions:

	hb_segment_properties_t
	HB_SEGMENT_PROPERTIES_DEFAULT
	hb_segment_properties_equal()
	hb_segment_properties_hash()

	hb_buffer_set_segment_properties()
	hb_buffer_get_segment_properties()

	hb_ot_layout_glyph_class_t

	hb_shape_plan_t
	hb_shape_plan_create()
	hb_shape_plan_create_cached()
	hb_shape_plan_get_empty()
	hb_shape_plan_reference()
	hb_shape_plan_destroy()
	hb_shape_plan_set_user_data()
	hb_shape_plan_get_user_data()
	hb_shape_plan_execute()

	hb_ot_shape_plan_collect_lookups()

API changes:

	Rename hb_ot_layout_feature_get_lookup_indexes() to
	hb_ot_layout_feature_get_lookups().

New header file:

	hb-shape-plan.h

And a bunch of prototyped but not implemented stuff.  Coming soon.
(Tests fail because of the prototypes right now.)

https://github.com/grigorig/ucdn

Also move UTF routines into a separate file, to be reused from shapers
that need it.

I don't expect ragel to be creating too much noise in its generated
output, and including this in-tree helps users right now.  We can
revisit this later if it proved to be too much trouble.

On Windows we don't care whether or not we link to libstdc++.
Seems to fix build with mingw32 on msys, as reported by Werner.

All of init/medi/fina/isol and rlig implemented.

Let there be dragons... ⻯

Import PortableFontInstance and add shaper stub.

And misc linking fixes.

Apparently even that doesn't make check-internal-symbols.sh happy with
mingw32.  Going to disable that for DLLs again, but hopefully the
export-file is doing *something*.

Used when there is no GPOS.

Add global shape_plan.  Unused so far.

Choose using shaper name "old".

Does not attempt to handle clusters in a Uniscribe- or HarfBuzz-compatible way;
just returns the original string indexes that CT maintains. These may even be
out-of-order in the case of reordrant glyphs.

Until I figure out the build issues.  Sigh...

New try.

To be used for cmap and advance caching if desired.

Also remove shaper_options argument to hb_shape_full().  That was
unused and for "future".  Let it go.

More shaper API coming in preparation for plan/planned API.

Not hooked up yet.

In preparation for Hangul shaper.