Unicode 9 updates (#70)

* 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

Makefile

@@ -19,9 +19,9 @@ UCFLAGS = $(CFLAGS) $(PICFLAG) $(C99FLAG) $(WCFLAGS) -DUTF8PROC_EXPORTS
 # not API compatibility: MAJOR should be incremented whenever *binary*
 # compatibility is broken, even if the API is backward-compatible
 # Be sure to also update these in MANIFEST and CMakeLists.txt!
-MAJOR=2
+MAJOR=3
 MINOR=0
-PATCH=1
+PATCH=0
 
 OS := $(shell uname)
 ifeq ($(OS),Darwin) # MacOS X