Ansible host variable fixes

[MoralCode]

This PR addresses the issue identified in https://github.com/knix-microfunctions/knix/issues/161 (and PR #162 which was accidentally closed as i was reorganizing git branches). It achieves this by updating some of the ansible configs to use a newer variable name to access the ssh hostname.

Approach

While I initially defaulted to using ansible_default_ipv4.address - it seems as though that created problems in the past, so I just stuck with using ansible_host and ensuring this is defined in inventory.cfg

Disclosure: I approached this fix with a largely automated find-and-replace strategy

Testing and possible drawbacks to this PR

I am able to get KNIX to install with this change (will be trying to run things soon). This changeset may have changed slightly more things than necessary but it shouldn't be too bad

fixes https://github.com/knix-microfunctions/knix/issues/161