[providers/facebook] configurable fields list for Graph API request

I also removed the "privacy" field from the default fields list which is
now deprecated and added the "place" field.

Author: trivoallan

README.md

@@ -17,7 +17,7 @@ Requirements:
 * PHP 5.5+
 * Curl library installed
 
-> 
+>
 * If you need PHP 5.3 support, use the 1.x version
 * If you need PHP 5.4 support, use the 2.x version
 
@@ -61,7 +61,7 @@ $info->width; //The width of the embed code
 $info->height; //The height of the embed code
 $info->aspectRatio; //The aspect ratio (width/height)
 
-$info->authorName; //The resource author 
+$info->authorName; //The resource author
 $info->authorUrl; //The author url
 
 $info->providerName; //The provider name of the page (Youtube, Twitter, Instagram, etc)
@@ -139,6 +139,7 @@ Used only for facebook events (not needed for posts, images, etc), to get inform
 Name | Type | Description
 -----|------|------------
 `key` | `string` | The access token used to get info from facebook graph API.
+`fields` | `string` | Comma-separated list of fields to query. Please refer to [Facebook documentation](https://developers.facebook.com/docs/graph-api/reference/event) for the full list of available fields.
 
 ## Example with all options:
 
@@ -174,6 +175,7 @@ $info = Embed::create($url, [
 
     'facebook' => [
         'key' => 'YOUR_KEY',
+        'fields' => 'field1,field2,field3' // default : cover,description,end_time,id,name,owner,place,start_time,timezone
     ],
 ]);
 ```

src/Embed.php

@@ -45,6 +45,11 @@ abstract class Embed
         'soundcloud' => [
             'key' => null,
         ],
+
+        'facebook' => [
+            'key' => null,
+            'fields' => 'cover,description,end_time,id,name,owner,place,start_time,timezone'
+        ]
     ];
 
     /**
@@ -131,7 +136,7 @@ private static function process(Url $url, array $config, DispatcherInterface $di
         if ($adapter::check($response)) {
             return new $adapter($response, $config, $dispatcher);
         }
-        
+
         if ($response->getError() === null) {
             $exception = new Exceptions\InvalidUrlException(sprintf("Invalid url '%s' (Status code %s)", (string) $url, $response->getStatusCode()));
         } else {

src/Providers/Api/Facebook.php

@@ -24,7 +24,7 @@ public function __construct(Adapter $adapter)
             if ($key) {
                 $endPoint = Url::create('https://graph.facebook.com/'.$id)
                     ->withQueryParameter('access_token', $key)
-                    ->withQueryParameter('fields', 'description,timezone,start_time,end_time,name,owner,privacy,id,cover');
+                    ->withQueryParameter('fields', $adapter->getConfig('facebook[fields]'));
 
                 $response = $adapter->getDispatcher()->dispatch($endPoint);