docs($exceptionHandler): include better example

The previous example overwrote the `$exceptionHandler` in order to re-throw the error. This is not
recommended, since it would leave the application in an inconsistent state and prevent proper
clean-up.
The new example simulates logging the error both to the backend and the console.

Fixes angular#14704

Author: gkalpak

src/ng/exceptionHandler.js

@@ -15,18 +15,21 @@
  *
  * ## Example:
  *
+ * The example below will overwrite the default `$exceptionHandler` in order to (a) log uncaught
+ * errors to the backend for later inspection by the developers and (b) to use `$log.warn()` instead
+ * of `$log.error()`.
+ *
  * ```js
- *   angular.module('exceptionOverride', []).factory('$exceptionHandler', function() {
- *     return function(exception, cause) {
- *       exception.message += ' (caused by "' + cause + '")';
- *       throw exception;
- *     };
- *   });
+ *   angular.
+ *     module('exceptionOverwrite', []).
+ *     factory('$exceptionHandler', ['$log', 'logErrorsToBackend', function($log, logErrorsToBackend) {
+ *       return function myExceptionHandler(exception, cause) {
+ *         logErrorsToBackend(exception, cause);
+ *         $log.warn(exception, cause);
+ *       };
+ *     });
  * ```
  *
- * This example will override the normal action of `$exceptionHandler`, to make angular
- * exceptions fail hard when they happen, instead of just logging to the console.
- *
  * <hr />
  * Note, that code executed in event-listeners (even those registered using jqLite's `on`/`bind`
  * methods) does not delegate exceptions to the {@link ng.$exceptionHandler $exceptionHandler}
@@ -36,7 +39,7 @@
  * `try { ... } catch(e) { $exceptionHandler(e); }`
  *
  * @param {Error} exception Exception associated with the error.
- * @param {string=} cause optional information about the context in which
+ * @param {string=} cause Optional information about the context in which
  *       the error was thrown.
  *
  */