For the jsonfile plugin, the path should be a local directory. This
directory needs to be readable by any user that would execute the
playbook. Since /var/lib/mistral may not be world readable, we should
use something in the user's home dir instead. This changes it to
~/.ansible/fact_cache
Change-Id: I8fa7127cf9ebb51ce4f090670ec2a45bcfcf77e8
Closes-Bug: #1873480