Support 1.9 UDM Firmware

User @a10kiloham updated to the v1.9 UDM firmware and discovered that the API requires host record address records need to have an ipVersion attribute set to "v4" or "v6".

This release adds that by default. It also makes some breaking changes.

(1) if fixes the name of the add script to add-host-records.sh to match the README
(2) it removes argument 3 and changes the usages to

add-host-record.sh {-f} {-v 4|6} <hostname>.<domain> <ipaddress>

  -f     FQDN only.  Sets registerNonQualified=false on the host record.  Defaults to true.
  -v     4 or 6.  Defaults to 4.  Ignored by UDM firmware < 1.9.

This incorporates PR #2 and fixes #1.

v1.0-rc1

First shared release.