### Please describe the problem.

When adding a video with "addurl", git-annex claims that quvi does not know how to download the url. When using "quvi get" on the same url the video gets downloaded.

This seems to be independent of the video hosting site and occured on all I tested.

### What steps will reproduce the problem?

Download a video with

    git annex addurl "[URL]"

and do the same with

    quvi get "[URL]"

.


### What version of git-annex are you using? On what operating system?

OS: Archlinux, fully updated

    git-annex version: 5.20131118-gc7e5cde
    build flags: Assistant Webapp Pairing S3 WebDAV Inotify DBus XMPP Feeds Quvi TDFA
    key/value backends: SHA256E SHA1E SHA512E SHA224E SHA384E SHA256 SHA1 SHA512 SHA224 SHA384 WORM URL
    remote types: git gcrypt S3 bup directory rsync web webdav glacier hook
    local repository version: 3
    default repository version: 3
    supported repository versions: 3 5
    upgrade supported from repository versions: 0 1 2 4


### Please provide any additional information below.

# Git-annex:

    user@asus aaa [master] % git annex addurl "https://www.youtube.com/watch?v=TUrQsK5ouSg"
    quvi v0.9.5
      built on 2013-11-12 17:02:06 +0000 for x86_64-unknown-linux-gnu
        with gcc, -march=x86-64 -mtune=generic -O2 -pipe -fstack-protector --param=ssp-buffer-size=4
      configuration: --prefix=/usr
    libquvi v0.9.4
      built on 2013-11-12 16:58:23 +0000 for x86_64-unknown-linux-gnu
        with gcc, -march=x86-64 -mtune=generic -O2 -pipe -fstack-protector --param=ssp-buffer-size=4
      configuration: --prefix=/usr
    libquvi-scripts v0.9.20131104
      configuration: --prefix=/usr --with-nsfw --with-geoblocked
    
    Copyright (C) 2012,2013  Toni Gundogdu <legatvs@gmail.com>
    quvi comes with ABSOLUTELY NO WARRANTY.  You may redistribute copies of
    quvi under the terms of the GNU Affero General Public License version 3
    or later. For more information, see <http://www.gnu.org/licenses/agpl.html>.
    
    To contact the developers, please mail to <quvi-devel@lists.sourceforge.net>
    
    Copyright (C) 2012,2013  Toni Gundogdu <legatvs@gmail.com>
    quvi comes with ABSOLUTELY NO WARRANTY.  You may redistribute copies of
    quvi under the terms of the GNU Affero General Public License version 3
    or later. For more information, see <http://www.gnu.org/licenses/agpl.html>.
    
    To contact the developers, please mail to <quvi-devel@lists.sourceforge.net>
    git-annex: quvi does not know how to download url https://www.youtube.com/watch?v=TUrQsK5ouSg

# Quvi:

    user@asus aaa [master] % quvi get "https://www.youtube.com/watch?v=TUrQsK5ouSg"
    file: GitAnnex Assistant Hak5 14223.mp4  [media]                                                       
      content length: 162.2Mi  content type: video/mp4  mode: resume
    copy: --=-  100%   488.9Ki/s  00:05:37

> git annex 5.20131127 is the first to support quvi 0.9. 
> (And only if built on a system with that version of quvi installed).
> Upgrade. [[done]] --[[Joey]]
