Computes all the glyphs that may be generated given a font and
set of Unicode characters.

The order of the Unicode characters is irrelevant.

Sample output:

behdad:util 0$ ./hb-ot-shape-closure Doulos\ SIL\ Regular.ttf f
f f_f

behdad:util 0$ ./hb-ot-shape-closure Doulos\ SIL\ Regular.ttf i
i

behdad:util 0$ ./hb-ot-shape-closure Doulos\ SIL\ Regular.ttf fi
f f_i f_f_i f_f i

behdad:util 0$ ./hb-ot-shape-closure DroidNaskh-Regular.ttf ب
uni0628 uni0628.init uni0628.medi uni0628.fina

behdad:util 0$ ./hb-ot-shape-closure DroidNaskh-Regular.ttf ا
uni0627 uni0627.fina

behdad:util 0$ ./hb-ot-shape-closure DroidNaskh-Regular.ttf با
uni0627 uni0627.fina uni0628 uni0628.init uni0628.medi uni0628.fina

behdad:util 0$ ./hb-ot-shape-closure DroidNaskh-Regular.ttf با --no-glyph-names
5 6 133 134 135 136

Testing with old Deva spec this reduces failures.
Test sequence: U+0915,U+094D,U+0930.

This reverts commit 0831061e.

The spec doesn't say contextual matching should be done this way,
and AOTS doesn't do it either.  It was inherited from old HarfBuzz.
Remove it.

Ended up not using terminal size after all.

One less argument to type in typical testing workflow!

Most common usecase of hb-view is to test rendering of short words for
testing / inspection.  Not having to type "--font-size 150" each time
isn't such a bad idea...

Just default to it.  Added "--help" instead to get usage.

And this, concludes the HarfBuzz Massala Hackfest.

I like to specially thank Jonathan Kew for doing all the decription and
letting me get commit points.

Bengali is at *just* above 5% now.

Error down from 20% to 7%.

Yep, on Bengali now!

For dotted-circle independent clusters, Uniscribe does no Reph shaping
for the exact sequence Ra+Halant+25CC.  Which also is the only possible
sequence with 25CC at the end.

Uniscribe allows multiple Halant+Consonant after a Vowel.
Tests:
↦       * U+0905,U+094D,U+092B,U+094D,930,94d,930

Uniscribe allows up to two nuktas per consonant and one per matra. It does so
indepent of whether the consonant already has a nukta in it.  Tests:

        * U+0916,U+093C,U+0941
        * U+0959,U+093C,U+0941
        * U+0916,U+093C,U+093C,U+0941
        * U+0959,U+093C,U+093C,U+0941
        * U+0916,U+093C,U+093C,U+093C,U+0941
        * U+0959,U+093C,U+093C,U+093C,U+0941
        * 915,93c,93c,,94d,U+0916,U+093C,U+093C,U+093e,93c,93c

See comments.