Update to Unicode 13.0.0.

doc/html/pcre2syntax.html

@@ -223,6 +223,7 @@ Caucasian_Albanian,
 Chakma,
 Cham,
 Cherokee,
+Chorasmian,
 Common,
 Coptic,
 Cuneiform,
@@ -230,6 +231,7 @@ Cypriot,
 Cyrillic,
 Deseret,
 Devanagari,
+Dives_Akuru,
 Dogra,
 Duployan,
 Egyptian_Hieroglyphs,
@@ -261,6 +263,7 @@ Kannada,
 Katakana,
 Kayah_Li,
 Kharoshthi,
+Khitan_Small_Script,
 Khmer,
 Khojki,
 Khudawadi,
@@ -350,6 +353,7 @@ Ugaritic,
 Vai,
 Wancho,
 Warang_Citi,
+Yezidi,
 Yi,
 Zanabazar_Square.
 </P>