Moving the precomposed Hangul syllables (U+AC00 ~) rendering to hangul-xft

[Changwoo Ryu <cwryu debian org>]

I was to move the precomposed Hangul syllable (U+AC00~) area to
hangul-xft from basic-xft, just for a better Unicode implementation.
These syllables don't always 1:1 match to U+AC00 glyphs:

- One of Hangul tone marks can follow any precomposed syllable.  Then
the syllable and the tone should be treated as a single cluster.
- A precomposed syllable can be processed as _same_ as "L V" or "L V T"
jamo sequence; it means, a precomposed syllable and some
preceding/following jamos form a syllable which is a single cluster.

Tell me any issue on it.  If there's no other problem and time
permits, I'll hack on this in a few days.

-- 
Changwoo Ryu

Cc'ing is encouraged