* Updates for Unicode 9.0.0 TR29 Changes
- New rules GB10/(12/13) are used to combine emoji-zwj sequences/
(force grapheme breaks every two RI codepoints). Unfortunately this
breaks statelessness of grapheme-boundary determination. Deal with
this by ignoring the problem in utf8proc_grapheme_break, and by
hacking in a special case in decompose
- ZWJ moved to its own boundclass, update what is now GB9 accordingly.
- Add comments to indicate which rule a given case implements
- The Number of bound classes Now exceeds 4 bits, expand to 8 and
reorganize fields
* Import Unicode 9 data
* Update Grapheme break API to expose state override
* Bump MAJOR version
Revise the script to directly read fontforge font files, which are
generated in the makefile. This permits overriding the fontforge path
during the build, and executing fontforge in parallel with make -j.
Avoid duplicating download URLs in the script, which ensures that the
script itself works without network access, e.g., when downloading the
data files on a developer machine with network access and executing the
script on a build machine without network access.
