[arabic-table] Read Blocks.txt and shuffle code around

No functional change.

src/hb-ot-shape-complex-arabic-table.hh

diff --git a/src/hb-ot-shape-complex-arabic-table.hh b/src/hb-ot-shape-complex-arabic-table.hh
index 730a275..3375266 100644
--- a/src/hb-ot-shape-complex-arabic-table.hh
+++ b/src/hb-ot-shape-complex-arabic-table.hh
@@ -2,12 +2,14 @@
 /*
  * The following table is generated by running:
  *
- *   ./gen-arabic-table.py ArabicShaping.txt UnicodeData.txt
+ *   ./gen-arabic-table.py ArabicShaping.txt UnicodeData.txt Blocks.txt
  *
  * on files with these headers:
  *
  * # ArabicShaping-6.2.0.txt
  * # Date: 2012-05-15, 21:05:00 GMT [KW]
+ * # Blocks-6.2.0.txt
+ * # Date: 2012-05-14, 22:42:00 GMT [KW, LI]
  * UnicodeData.txt does not have a header.
  */
 
@@ -18,7 +20,7 @@
 static const uint8_t joining_table[] =
 {
 
-  /* Arabic Characters */
+  /* Arabic */
 
   JOINING_TYPE_U, /* 0600; ARABIC NUMBER SIGN; U; No_Joining_Group */
   JOINING_TYPE_U, /* 0601; ARABIC SIGN SANAH; U; No_Joining_Group */
@@ -277,7 +279,7 @@
   JOINING_TYPE_X, /* 06FE */
   JOINING_TYPE_D, /* 06FF; KNOTTED HEH WITH INVERTED V ABOVE; D; KNOTTED HEH */
 
-  /* Syriac Characters */
+  /* Syriac */
 
   JOINING_TYPE_X, /* 0700 */
   JOINING_TYPE_X, /* 0701 */
@@ -360,7 +362,7 @@
   JOINING_TYPE_D, /* 074E; SOGDIAN KHAPH; D; KHAPH */
   JOINING_TYPE_D, /* 074F; SOGDIAN FE; D; FE */
 
-  /* Arabic Supplement Characters */
+  /* Arabic Supplement */
 
   JOINING_TYPE_D, /* 0750; DOTLESS BEH WITH HORIZONTAL 3 DOTS BELOW; D; BEH */
   JOINING_TYPE_D, /* 0751; BEH WITH 3 DOTS ABOVE; D; BEH */
@@ -411,7 +413,7 @@
   JOINING_TYPE_D, /* 077E; SEEN WITH INVERTED V ABOVE; D; SEEN */
   JOINING_TYPE_D, /* 077F; KAF WITH 2 DOTS ABOVE; D; KAF */
 
-  /* N'Ko Characters */
+  /* Thaana */
 
   JOINING_TYPE_X, /* 0780 */
   JOINING_TYPE_X, /* 0781 */
@@ -477,6 +479,9 @@
   JOINING_TYPE_X, /* 07BD */
   JOINING_TYPE_X, /* 07BE */
   JOINING_TYPE_X, /* 07BF */
+
+  /* NKo */
+
   JOINING_TYPE_X, /* 07C0 */
   JOINING_TYPE_X, /* 07C1 */
   JOINING_TYPE_X, /* 07C2 */
@@ -536,14 +541,14 @@
   JOINING_TYPE_X, /* 07F8 */
   JOINING_TYPE_X, /* 07F9 */
   JOINING_TYPE_C, /* 07FA; NKO LAJANYALAN; C; No_Joining_Group */
-
-  /* Mandaic Characters */
-
   JOINING_TYPE_X, /* 07FB */
   JOINING_TYPE_X, /* 07FC */
   JOINING_TYPE_X, /* 07FD */
   JOINING_TYPE_X, /* 07FE */
   JOINING_TYPE_X, /* 07FF */
+
+  /* Samaritan */
+
   JOINING_TYPE_X, /* 0800 */
   JOINING_TYPE_X, /* 0801 */
   JOINING_TYPE_X, /* 0802 */
@@ -608,6 +613,9 @@
   JOINING_TYPE_X, /* 083D */
   JOINING_TYPE_X, /* 083E */
   JOINING_TYPE_X, /* 083F */
+
+  /* Mandaic */
+
   JOINING_TYPE_R, /* 0840; MANDAIC HALQA; R; No_Joining_Group */
   JOINING_TYPE_D, /* 0841; MANDAIC AB; D; No_Joining_Group */
   JOINING_TYPE_D, /* 0842; MANDAIC AG; D; No_Joining_Group */
@@ -633,9 +641,6 @@
   JOINING_TYPE_U, /* 0856; MANDAIC DUSHENNA; U; No_Joining_Group */
   JOINING_TYPE_U, /* 0857; MANDAIC KAD; U; No_Joining_Group */
   JOINING_TYPE_U, /* 0858; MANDAIC AIN; U; No_Joining_Group */
-
-  /* Arabic Extended-A Characters */
-
   JOINING_TYPE_X, /* 0859 */
   JOINING_TYPE_X, /* 085A */
   JOINING_TYPE_X, /* 085B */
@@ -707,6 +712,9 @@
   JOINING_TYPE_X, /* 089D */
   JOINING_TYPE_X, /* 089E */
   JOINING_TYPE_X, /* 089F */
+
+  /* Arabic Extended-A */
+
   JOINING_TYPE_D, /* 08A0; DOTLESS BEH WITH V BELOW; D; BEH */
   JOINING_TYPE_X, /* 08A1 */
   JOINING_TYPE_D, /* 08A2; HAH WITH DOT BELOW AND 2 DOTS ABOVE; D; HAH */