QQ: dirty fix #153
Acfun & Bilibili: fix #148
add suport for songtaste
fix trailing whitespace errors
add SongTaste to README
xiami album 3332 UnicodeEncodeError
Google+: use Content-Disposition filename
remove test for Google+
avoid using the libav fork of FFmpeg, as in #159
supporting both ffmpeg 1.x and libav, fix #159
using Content-Range; workaround of #160