le-autoupgrade: Set up /etc/apt/preferences

The postinst script now configures the apt_preferences file
to give a high priority (1100) to the packages from our repository.
Signed-off-by: Lucas Manika Koeb <lmk08@c3sl.ufpr.br>

le-autoupgrade/pacote/DEBIAN/postinst

+#!/bin/bash
+
+# Copyright (C) 2012 Centro de Computacao Cientifica e Software Livre
+# Departamento de Informatica - Universidade Federal do Parana - C3SL/UFPR
+#
+# This file is part of le-autoupgrade
+#
+# le-autoupgrade is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+
+# Setup /etc/apt/preferences to give a high priority to our repository:
+# Pin-Priority should be > 1000, this way our version will be installed
+# even if this mean a package downgrade.
+
+PREFERENCES="/etc/apt/preferences"
+
+echo "" >> $PREFERENCES
+echo "Package: *" >> $PREFERENCES
+echo "Pin: origin \"windu.c3sl.ufpr.br\"" >> $PREFERENCES
+echo "Pin-Priority: 1100" >> $PREFERENCES
+
+exit 0