Fix pluggable scripting engine lookup, simplify implementation, and add unit tests.

README.html

@@ -301,7 +301,7 @@ The standard use of JSR-223 scripting engines may be used:
 
 <pre>
 	ScriptEngineManager mgr = new ScriptEngineManager();
-	ScriptEngine e = mgr.getEngineByExtension(".lua");
+	ScriptEngine e = mgr.getEngineByName("luaj");
 	e.put("x", 25);
 	e.eval("y = math.sqrt(x)");
 	System.out.println( "y="+e.get("y") );
@@ -846,6 +846,7 @@ Files are no longer hosted at LuaForge.
 
 <tr valign="top"><td>&nbsp;&nbsp;<b>3.0-beta1</b></td><td><ul>
 <li>Fix bug that didn't read package.path from environment.</li>
+<li>Fix pluggable scripting engine lookup, simplify implementation, and add unit tests.</li>
 
 </ul></td></tr>
 </table></td></tr></table>