HG-385 P2 fix: added InvalidDataApiException to autloader and added fallback to navigation exception

There are some wikias with broken navigation data and not loaded `ApiExceptions.php` file which resulted with a white page for some users using Mercury. First step was to add missing exception to autoloader and then handle the navigation exception.
You can pass ``Exception`` instance via:

```
[
  'exception' => $e
]
```