support zsh completion
add zsh completion support into Makefile
[niconico] Fix ignored --netrc flag

See issue #3753
release 2014.10.12
[options] Mention login in --username documentation (#3753)
[options] Consistent formatting and general niceness
Merge remote-tracking branch 'xu-cheng/zsh-completion'
[zsh-completion] Ignore generated file (#3890)
[youtube] Download DASH manifest by default (Closes #3887)
[youtube] Add support for format 278
[kontrtube] Fix video title extraction
[huffpost] Modernize
Merge remote-tracking branch 'Dineshs91/KontrTube-fix'
[ffmpeg] Improve format merging (Closes #3935)
release 2014.10.13
[condenast] Add support for embedded videos (Closes #3929)
[brightcove] Add a test for playlists
[extractor/common] Fix dumping requests with long file abspath on Windows
[mixcloud] Output downloading progress
[ted] Add support for external videos (fixes #3948)