do not install lam.conf if other config files exist

lam-packaging/debian/postinst

@@ -51,9 +51,12 @@ chown www-data /var/lib/ldap-account-manager/tmp/internal
 chmod 700 /var/lib/ldap-account-manager/tmp
 chown -R www-data /var/lib/ldap-account-manager/config
 chmod 700 /var/lib/ldap-account-manager/config
-if [ ! -f /var/lib/ldap-account-manager/config/lam.conf ]; \
-   then cp /var/lib/ldap-account-manager/config/unix.conf.sample /var/lib/ldap-account-manager/config/lam.conf; \
-	chown www-data /var/lib/ldap-account-manager/config/lam.conf; fi
+ls -l /var/lib/ldap-account-manager/config/*.conf &> /dev/null
+cfgFilesExist=$?
+if [ $cfgFilesExist != 0 ]; then
+  cp /var/lib/ldap-account-manager/config/unix.conf.sample /var/lib/ldap-account-manager/config/lam.conf;
+	chown www-data /var/lib/ldap-account-manager/config/lam.conf;
+fi
 chmod 600 /var/lib/ldap-account-manager/config/*.conf
 if [ "$1" = "configure" ]; then
     db_get "ldap-account-manager/alias"