and CFF retain-gids fixes

along with api tests & expected results

Fixes https://github.com/harfbuzz/harfbuzz/issues/1535

[subset] Update the subset fuzzer to get  options to use from test case.

[subset] Update the subset fuzzer to determine which options to use based on data in the fuzzing test case.
Add support for toggling retain_gids.

[subset] Add --retain-gids option to the subsetter.

[subset] Re-add glyphs array to subset plan, with new name 'glyphs_deprecated'. Switch CFF subsetting to use it.

Re-implement HMTX/VMTX subsetting. Update it to support glyph renumbering and simplify the implementation.

Update maxp to use the correct num glyphs.

- Extract code out into helper methods in several places.
- Bundle loca address, size and is short into a struct.

[skip ci]

[skip ci]

[skip ci]

c:\projects\harfbuzz\src\hb-ot-color-cbdt-table.hh(59): warning C4146: unary minus operator applied to unsigned type, result still unsigned [C:\projects\harfbuzz\build\harfbuzz.vcxproj]