[goshgay] Fix extraction

isFamilyFriendly no longer exists in the webpage and I can't find
another indicator.

youtube_dl/extractor/goshgay.py

@@ -14,13 +14,13 @@ class GoshgayIE(InfoExtractor):
     _VALID_URL = r'https?://www\.goshgay\.com/video(?P<id>\d+?)($|/)'
     _TEST = {
         'url': 'http://www.goshgay.com/video299069/diesel_sfw_xxx_video',
-        'md5': '027fcc54459dff0feb0bc06a7aeda680',
+        'md5': '4b6db9a0a333142eb9f15913142b0ed1',
         'info_dict': {
             'id': '299069',
             'ext': 'flv',
             'title': 'DIESEL SFW XXX Video',
             'thumbnail': 're:^http://.*\.jpg$',
-            'duration': 79,
+            'duration': 80,
             'age_limit': 18,
         }
     }
@@ -47,5 +47,5 @@ class GoshgayIE(InfoExtractor):
             'title': title,
             'thumbnail': thumbnail,
             'duration': duration,
-            'age_limit': self._family_friendly_search(webpage),
+            'age_limit': 18,
         }