feature(translationCache): rework 63eae7f making cache customizable

* `$translationCache` isn't be hardcoded anymore (can be replaced with other cache implementations)
* `$translationCache` could be `true` for AJS internal default

New feature usage:

```js
$translateProvider.useLoaderCache(false) // disable any cache (default behaviour)
$translateProvider.useLoaderCache(true) // use `$http({cache: true})
$translateProvider.useLoaderCache() // use our internal default `$translationCache` (actually `$translateProvider.useLoaderCache('$translationCache')`
$translateProvider.useLoaderCache('cacheService') // use the given identifying cacheService
$translateProvider.useLoaderCache(cacheService) // use the cacheService
```

This also introduces the feature loaders are provided with the option `$http` for additional standard params. Currently, only `$http.cache` could be defined.