chore: Add *.log & playbooks/.facts to .gitignore
chore: Add *.log & playbooks/.facts to .gitignore

The default ansible config in 'playbooks/ansible.cfg' sets log_path to
'./ansible.log' and fact_caching_connection to './.facts/'. Neither
'*.log' files nor the '.facts' directory need to be tracked by git.

Change-Id: Ie7bc46b83bcfb55e32020a60e24054d2bb2fcdf1

open-power-ref-design-toolkit/cluster-genesis,open-power-ref-design-toolkit/cluster-genesis