Major: 0.4.7

New Features:
1. Enabled FFMpeg on Mac OS X.
2. Add file association suggest on Mac OS X.
Major: 0.4.7

Merge:
1. Apply merge.
Major: 0.4.7

Updates:
1. Support get the downloader’s name.
Major: 0.4.7

New Features:
1. Support download Baidu lyrics.