Split ary to ary-latn and ary-arab

The Arabic script is more common for publishing in this language,
but the Latin script is used occasionally, too.
The autonym ed-dārija was requested by the editors of
the incubator Wikipedia in this language, and I confirmed
that it's good with an external expert.

This addresses #74.

This is similar to #75 by SADIQUI.

data/langdb.yaml

@@ -26,7 +26,9 @@ languages:
   arn: [Latn, [AM], mapudungun]
   aro: [Latn, [AM], Araona]
   arq: [Arab, [AF, ME], جازايرية]
-  ary: [Latn, [AF, ME], Maġribi]
+  ary: [Arab, [AF, ME], الدارجة]
+  ary-arab: [ary]
+  ary-latn: [Latn, [AF, ME], ed-dārija]
   arz: [Arab, [AF, ME], مصرى]
   as: [Beng, [AS], অসমীয়া]
   ase: [Sgnw, [AM], American sign language]