Revert lost translations in es, gl, ja

Looks like Jacques needs to enable these locales on his system.

docs/ja_JP.UTF-8/html/SVG.html

@@ -17,16 +17,16 @@
             width="205"
             height="210"
             alt="Tux Paint"><br>
-        version 0.9.27<br/>
+        バージョン 0.9.27<br/>
         SVG Documentation      </h1>
 
       <p>
-        Copyright &copy; 2007-2021 by various contributors; see AUTHORS.<br>
+        Copyright &copy; 2007-2021 by various contributors; "AUTHORS" 参照.<br>
         <a href="http://www.tuxpaint.org/">http://www.tuxpaint.org/</a>
       </p>
 
       <p>
-        March  9, 2021      </p>
+        2021年3月 9日      </p>
     </center>
 
     <hr>