Fix type validation for fmod and dmod

Since the dmod and fmod setter take a string as argument and convert them to a
base 8 integer, we don't need to check and convert in integer with the
configobj validator.

Signed-off-by: Sébastien Luttringer <sebastien.luttringer@smartjog.com>
Remove reference to Debian package sorting algorithm

Signed-off-by: Sébastien Luttringer <sebastien.luttringer@smartjog.com>