modules file is not a conf file, rather a sample in /usr/share/dahdi
add changelog entry
keep existing dahdi modules conf file

dpkg still considers /etc/dahdi/modules as owned by dahdi even after upgrade.
dpkg-maintscript-helper rm_conffile will rename target file differently
depending if file has been modified (.dpkg-backup) or not (.dpkg-remove).
fix whitespaces
Merge pull request #1 from xivo-pbx/modules-not-conf

Modules not conf