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!

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

Can be -1 for NUL-terminated string.  This is useful for passing parts
of a larger string to a function without having to copy or modify the
string first.

Affected functions:

	hb_tag_t hb_tag_from_string()
	hb_direction_from_string()
	hb_language_from_string()
	hb_script_from_string()