Add 'yankshort' option.

common/locale/en-US/options.xml

@@ -1811,6 +1811,17 @@
     </description>
 </item>
 
+<item>
+    <tags>'ys' 'yankshort'</tags>
+    <spec>'yankshort' 'ys'</spec>
+    <type>&option.yankshort.type;</type>
+    <default>&option.yankshort.default;</default>
+    <description>
+        <p>Yank the canonical short URL of a web page where provided.</p>
+    </description>
+</item>
+
+
 </document>
 
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