Force english as the only supported language for YouTube (#196)

Author: mauriciocolli

extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/YoutubeService.java

@@ -139,13 +139,14 @@ public CommentsExtractor getCommentsExtractor(ListLinkHandler urlIdHandler)
 
     // https://www.youtube.com/picker_ajax?action_language_json=1
     private static final List<Localization> SUPPORTED_LANGUAGES = Localization.listFrom(
-            "af", "am", "ar", "az", "be", "bg", "bn", "bs", "ca", "cs", "da", "de",
-            "el", "en", "en-GB", "es", "es-419", "es-US", "et", "eu", "fa", "fi", "fil", "fr",
-            "fr-CA", "gl", "gu", "hi", "hr", "hu", "hy", "id", "is", "it", "iw", "ja",
-            "ka", "kk", "km", "kn", "ko", "ky", "lo", "lt", "lv", "mk", "ml", "mn",
-            "mr", "ms", "my", "ne", "nl", "no", "pa", "pl", "pt", "pt-PT", "ro", "ru",
-            "si", "sk", "sl", "sq", "sr", "sr-Latn", "sv", "sw", "ta", "te", "th", "tr",
-            "uk", "ur", "uz", "vi", "zh-CN", "zh-HK", "zh-TW", "zu"
+            "en-GB"
+//            "af", "am", "ar", "az", "be", "bg", "bn", "bs", "ca", "cs", "da", "de",
+//            "el", "en", "en-GB", "es", "es-419", "es-US", "et", "eu", "fa", "fi", "fil", "fr",
+//            "fr-CA", "gl", "gu", "hi", "hr", "hu", "hy", "id", "is", "it", "iw", "ja",
+//            "ka", "kk", "km", "kn", "ko", "ky", "lo", "lt", "lv", "mk", "ml", "mn",
+//            "mr", "ms", "my", "ne", "nl", "no", "pa", "pl", "pt", "pt-PT", "ro", "ru",
+//            "si", "sk", "sl", "sq", "sr", "sr-Latn", "sv", "sw", "ta", "te", "th", "tr",
+//            "uk", "ur", "uz", "vi", "zh-CN", "zh-HK", "zh-TW", "zu"
     );
 
     // https://www.youtube.com/picker_ajax?action_country_json=1

extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/extractors/YoutubeChannelExtractor.java

@@ -48,7 +48,7 @@
 public class YoutubeChannelExtractor extends ChannelExtractor {
     /*package-private*/ static final String CHANNEL_URL_BASE = "https://www.youtube.com/channel/";
     private static final String CHANNEL_FEED_BASE = "https://www.youtube.com/feeds/videos.xml?channel_id=";
-    private static final String CHANNEL_URL_PARAMETERS = "/videos?view=0&flow=list&sort=dd&live_view=10000&gl=US&hl=en";
+    private static final String CHANNEL_URL_PARAMETERS = "/videos?view=0&flow=list&sort=dd&live_view=10000";
 
     private Document doc;