Merge remote-tracking branch 'daohoangson/zing-mp3'

diff --combined youtube_dl/extractor/__init__.py
index 43185345ec33a52f1fd1c2cf12bbb54f71781cc1,3a520908bb272ef57339d7480eec0acfd92c0b64..fb5e6ac77d5680238579a765c0f341a5cff0b68c
--- 1/youtube_dl/extractor/__init__.py
--- 2/youtube_dl/extractor/__init__.py
+++ b/youtube_dl/extractor/__init__.py
@@@ -511,6 -511,10 +511,10 @@@ from .youtube import 
      YoutubeWatchLaterIE,
  )
  from .zdf import ZDFIE
+ from .zingmp3 import (
+     ZingMp3SongIE,
+     ZingMp3AlbumIE,
+ )
  
  _ALL_CLASSES = [
      klass
@@@ -529,4 -533,4 +533,4 @@@ def gen_extractors()
  
  def get_info_extractor(ie_name):
      """Returns the info extractor class with the given ie_name"""
 -    return globals()[ie_name+'IE']
 +    return globals()[ie_name + 'IE']