debian

As discussed on the mailing list[1], ring-daemon will no longer install
repositories for the user. The recommended way of using our packages is
installing the repositories and then installing ring with your package
manager. Users that decide to install packages manually can still do so
but they will have to handle updates themselves.

1. https://lists.savoirfairelinux.net/pipermail/ring/2016-July/002620.html

Change-Id: If581b7df26f24e5cc61b69c375b03fb74b57c996
Tuleap: #591