Update hiera yaml to version 5

[mmoll]

Pull request acceptance prerequisites:

• Signed the CLA (if not already signed)
• Rebased/up-to-date with base branch
• Updated CHANGELOG.md with patch notes (if necessary)
• Any relevant docs (README.markdown or inline documentation) updated (if necessary)
• Updated CONTRIBUTORS (if you would like attribution)
• Tests pass CI

[tylerjl]

Thanks for the PR @mmoll - do you happen to have a link to the Puppet support lifecycle? I'm on board with bumping the minimum required Puppet version if versions < 4.9 are end-of-life (but I can't find documentation about it anywhere)

[mmoll]

@tylerjl Unfortunately there seem to be no notes about this, but https://ask.puppet.com/question/33472/puppet-4-open-source-end-of-life-eol/ and https://groups.google.com/forum/#!topic/puppet-users/78ZcVVyuIMQ suggests that even the whole 4.x series is EOL now. However, the 4.10.x branch in Puppetlabs' repo seems still to get updates, (which is still > 4.9).

[tylerjl]

Alright @mmoll I hopped into the Puppet community Slack and talked with a product manager and 4.x is dead after the start of 2019, but I don't see a reason to kill 4.x entirely yet - but at the very least moving a version that shipped Hiera 5 sounds reasonable. They suggested supporting >= 4.10 since that's a much more recently-supported version of 4.x, so if you're in agreement, could I ask:

1. Bump the minimum version (and associated tests) to point at 4.10 instead of 4.9, since it sounds like 4.10 is the way to go
2. Make a small note about raising the minimum required Puppet version in the module's CHANGELOG
3. Do the same for the puppet-elasticsearch module PR (Update hiera yaml to version 5 puppet-elasticsearch#1010)?

Thanks for taking the initiative on version bumping here, community help is greatly appreciated 🙏

[tylerjl]

Also side-note (that I'm sure you already discerned), the failing Travis test is unrelated so with the changes I mentioned above I'm happy to merge this.

[mmoll]

@tylerjl Sure, what's the next version for the changelog? 6.3.2? 6.4.0? 7.0.0? :)

[mmoll]

aw, sorry, ignore the qestion, I see the placeholder now

[mmoll]

done.

[tylerjl]

Thanks a million @mmoll 🙏