[weibo] Remove the extractor

The Weibo weishipin (微視頻, tiny videos) service is dead and now all
videos are hosted on Sina videos, which is covered by sina.py

youtube_dl/extractor/weibo.py

@@ -1,49 +0,0 @@
-# coding: utf-8
-from __future__ import unicode_literals
-
-import re
-
-from .common import InfoExtractor
-
-
-class WeiboIE(InfoExtractor):
-    """
-    The videos in Weibo come from different sites, this IE just finds the link
-    to the external video and returns it.
-    """
-    _VALID_URL = r'https?://video\.weibo\.com/v/weishipin/t_(?P<id>.+?)\.htm'
-
-    _TEST = {
-        'url': 'http://video.weibo.com/v/weishipin/t_zjUw2kZ.htm',
-        'info_dict': {
-            'id': '98322879',
-            'ext': 'flv',
-            'title': '魔声耳机最新广告“All Eyes On Us”',
-        },
-        'params': {
-            'skip_download': True,
-        },
-        'add_ie': ['Sina'],
-    }
-
-    # Additional example videos from different sites
-    # Youku: http://video.weibo.com/v/weishipin/t_zQGDWQ8.htm
-    # 56.com: http://video.weibo.com/v/weishipin/t_zQ44HxN.htm
-
-    def _real_extract(self, url):
-        mobj = re.match(self._VALID_URL, url, flags=re.VERBOSE)
-        video_id = mobj.group('id')
-        info_url = 'http://video.weibo.com/?s=v&a=play_list&format=json&mix_video_id=t_%s' % video_id
-        info = self._download_json(info_url, video_id)
-
-        videos_urls = map(lambda v: v['play_page_url'], info['result']['data'])
-        # Prefer sina video since they have thumbnails
-        videos_urls = sorted(videos_urls, key=lambda u: 'video.sina.com' in u)
-        player_url = videos_urls[-1]
-        m_sina = re.match(r'https?://video\.sina\.com\.cn/v/b/(\d+)-\d+\.html',
-                          player_url)
-        if m_sina is not None:
-            self.to_screen('Sina video detected')
-            sina_id = m_sina.group(1)
-            player_url = 'http://you.video.sina.com.cn/swf/quotePlayer.swf?vid=%s' % sina_id
-        return self.url_result(player_url)