standardize configuration for tags and invalidators

fix #33

i differ from what we discussed a bit:


```yaml
fos_http_cache:
    cache_control:
        -
            match:
                ...
            headers:
                ...
    cache_manager:
        ...
        tag_map:
            -
                match:
                    path: ^/news
                tags: [news-section]
                tag_expressions: ...
        route_invalidators:
            -
                match:
                    ...
                routes:
                    ...
```

with the route invalidators, i wonder why we limit that to invalidate routes, we could also support paths there, to have the same features as the annotations.
this would also work as
```
'routes' => array(
    'invalidate_route' => array(),
),
```
right?