Add context grabbing and things that depend on it

mining.html

@@ -15,7 +15,7 @@ body
 </head>
 
 <body lang="ja">
-<p>Tab separated values. Spelling, readings, definitions, JMdict numeric ID.</p>
+<p>Tab separated values. Spelling, readings, definitions, (if stored: looked up text, sentence, location in sentence), JMdict numeric ID.</p>
 <input type=button id=reset value="Reset"/>
 <textarea id="field" style="width:100%; height:calc(100% - 70px);"></textarea>
 </body>