docs(error/nobase): Added trailing slash for base path

Trailing slash seems to be necessary, otherwise `$routeProvider` does not match routes correctly. Following is not matched:

URL http://www.example.com/b/foo/1234
`<base href="/b/foo">`
```
$routeProvider.when('/:id', {
            templateUrl: '/view/path.html',
            controller: 'MyCtrl',
            reloadOnSearch: false
        });
```