use aptitude for debian based systems

use aptitude for debian based systems

The function to check wether we need to install packages was using
dpkg-query which was gives wrong output on Debian 5

Also, the apt-get has been replaced with aptitude because aptitude
is now the preferred way to handle packages on Debian

(closes issue #15570)
Reported by: mvanbaak
Patches:
      2009072400_installprereq-aptitude.diff uploaded by mvanbaak (license 7)

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@208542 65c4cc65-6c06-0410-ace0-fbb531ad65f3