Like hb-view, but prints out buffer contents.

The output format is kinda cryptic.  Suggestions welcome.

Bug 40953 - fail compile git: make[2]: *** [hb_view-options.o] Error 1

Fixes bug with uniscribe not handling GIGANTIC sizes.

Make --font-file accept "-" to mean stdin, and have it work
in Windows too!

Apparently there's no equivalent to "/dev/stdout", so write using
stdio to be able to output to stdout.

Now we can use the same code to do other utils...

We now support using -1 for NUL-terminated strings.

In hb_ot_tag_from_language(), if first component of an unknown
language is three letters long, use it directly as OpenType language
tag (after case conversion and padding).

Doesn't seem to be slower.