CONFDB: Add passwd_files and group_files options
Add new options to the files provider allowing an administrator to
configure the files provider to read and monitor multiple or
non-standard passwd and group file sources. These options default to
/etc/passwd and /etc/group when unset.
Reviewed-by: Pavel Březina <pbrezina@redhat.com>
Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>