Merge branch 'master' of github.com:rg3/youtube-dl

diff --combined youtube_dl/YoutubeDL.py
index 3df653c5d030253ef5bc09f8f43db30db2b111a8,b510831542d8e9ee68194a9fe3120ecf108dc142..d1618da7914b08ccad26a9ff9a9035d2efc48ea0
--- 1/youtube_dl/YoutubeDL.py
--- 2/youtube_dl/YoutubeDL.py
+++ b/youtube_dl/YoutubeDL.py
@@@ -264,7 -264,7 +264,7 @@@ class YoutubeDL(object)
              self.report_error(u'Erroneous output template')
              return None
          except ValueError as err:
 -            self.report_error(u'Insufficient system charset ' + repr(preferredencoding()))
 +            self.report_error(u'Error in output template: ' + str(err) + u' (encoding: ' + repr(preferredencoding()) + ')')
              return None
  
      def _match_entry(self, info_dict):
@@@ -547,7 -547,7 +547,7 @@@
                  try:
                      success = self.fd._do_download(filename, info_dict)
                  except (OSError, IOError) as err:
-                     raise UnavailableVideoError()
+                     raise UnavailableVideoError(err)
                  except (compat_urllib_error.URLError, compat_http_client.HTTPException, socket.error) as err:
                      self.report_error(u'unable to download video data: %s' % str(err))
                      return