Update the module to use the latest version of Graylog.

[malcyon]

I am updating this module, since it hasn't been touched in a while.

Things I have changed:

• The Puppet Vagrant VMs have not been updated in 5 years. I am changing them to just a base image and installing Puppet on them in the test script.
• Updated the OS versions we support in metadata.json. (Hopefully fixes PDK usage #33).
• Fixed issue in the test Vagrantfile where Elasticsearch won't install because it wants older dependencies.
• Fixed issue in the allinone class where Elasticsearch won't install due to the removal of multi-instance support.
• Updating default versions of MongoDB, Elasticsearch, and Graylog.
• Added some Elasticsearch configurations: oss => true and action.auto_create_index => false (Fixes Misc Config Updates #38)

[malcyon]

I cannot get MongoDB to install on Ubuntu 20.04 (See voxpupuli/puppet-mongodb#627). But our test does install Elasticsearch and Graylog just fine.

Everything works great on CentOS 8.

[malcyon]

Got Ubuntu 20.04 working by hacking the MongoDB module.