The inspect binding is needed because of the inspection of
validate_domain_name that has been introduced with commit
818db5cb4d for FreeIPA versions prior
to 4.7.
Removed unused user_input import from ipapython.ipautil. Added import
of DN from ipapython.dn. Set ntpinstance to None if timeconf or
sync_time could not be imported on older FreeIPA releases.
The installer logs have not been created using the ansible ipaclient,
ipareplica and ipaserver roles. This has been fixed and the installer
logs are created now.