Add an example how to adjust ts-loader settings

Author: Steveb-p

frontend/encore/typescript.rst

@@ -26,7 +26,19 @@ Encore, you're done!
 
 Any ``.ts`` files that you require will be processed correctly. You can
 also configure the `ts-loader options`_ via the ``enableTypeScriptLoader()``
-method. See the `Encore's index.js file`_ for detailed documentation and check
+method. 
+
+.. code-block:: javascript
+
+    Encore
+        .enableTypeScriptLoader(function(tsConfig) {
+            // You can use this callback function to adjust ts-loader settings
+            // https://github.com/TypeStrong/ts-loader/blob/master/README.md#loader-options
+            // For example:
+            // tsConfig.silent = false
+        })
+
+See the `Encore's index.js file`_ for detailed documentation and check
 out the `tsconfig.json reference`_ and the `Webpack guide about Typescript`_.
 
 If React is enabled (``.enableReactPreset()``), any ``.tsx`` file will also be