Smaller tables (#68)

* convert sequences to utf-16 (saves 25kb)

* store sequence length in properties instead using -1 termination (saves 10kb)

* cache index for slightly faster data creation

* store lower/upper/title mapping in sequence array (saves 25kb). Add utf8proc_totitle, as title_mapping cannot be used to get the title codepoint anymore. Rename xxx_mapping to xxx_seqindex, so programs assuming a value with the old meaning fail at compile time

* change combination array data type to uint16 (saves 40kb)

* merge 1st and 2nd comb index (saves 50kb)

* kill empty prefix/suffix in combination array (saves 50kb)

* there was no need to have a separate combination start array, it can be merged in a single array

* some fixes

* mark the table as const again

* and regen

test/printproperty.c

@@ -22,8 +22,7 @@ int main(int argc, char **argv)
                  "  uppercase_mapping = %x\n"
                  "  lowercase_mapping = %x\n"
                  "  titlecase_mapping = %x\n"
-                 "  comb1st_index = %d\n"
-                 "  comb2nd_index = %d\n"
+                 "  comb_index = %d\n"
                  "  bidi_mirrored = %d\n"
                  "  comp_exclusion = %d\n"
                  "  ignorable = %d\n"
@@ -35,11 +34,10 @@ int main(int argc, char **argv)
                  p->combining_class,
                  p->bidi_class,
                  p->decomp_type,
-                 p->uppercase_mapping,
-                 p->lowercase_mapping,
-                 p->titlecase_mapping,
-                 p->comb1st_index,
-                 p->comb2nd_index,
+                 utf8proc_toupper(c),
+                 utf8proc_tolower(c),
+                 utf8proc_totitle(c),
+                 p->comb_index,
                  p->bidi_mirrored,
                  p->comp_exclusion,
                  p->ignorable,