Update to Unicode 11.0.0

UCDN is not updated yet.
diff --git a/src/hb-common.cc b/src/hb-common.cc
index 956855c..a67fcf8 100644
--- a/src/hb-common.cc
+++ b/src/hb-common.cc
@@ -535,6 +535,11 @@
     /* Unicode-9.0 additions */
     case HB_SCRIPT_ADLAM:
 
+    /* Unicode-11.0 additions */
+    case HB_SCRIPT_HANIFI_ROHINGYA:
+    case HB_SCRIPT_OLD_SOGDIAN:
+    case HB_SCRIPT_SOGDIAN:
+
       return HB_DIRECTION_RTL;