contact-list-view: merge the audio and vido call column
contact-list-view: merge the audio and vido call column

Now that we display a context menu allowing to start audio and video call
there is no point to keep the 2 icons. Merge them to one column as they are
not just a hint saying that the contact supports audio and/or video.

GNOME/telepathy-account-widgets,Distrotech/telepathy-account-widgets,Distrotech/telepathy-account-widgets,GNOME/telepathy-account-widgets,GNOME/telepathy-account-widgets