Raise compatible puppet version from <7.0 to <8.0

[Fightbackman]

Affected Puppet, Ruby, OS and module versions/distributions

• Puppet: 7.X
• Ruby: -
• Distribution: any
• Module version: 6.0.0

How to reproduce (e.g Puppet code you use)

The module list only puppet versions <7.0 as compatible

What are you seeing

A warning by puppet-lint and problem resolvinh dependencies for the puppet7 environment.
The module itself seems to work without problems in my setup on debian buster and stretch systems.

What behaviour did you expect instead

Puppet module compatible for puppet version <8.0

Output log

Any additional information you'd like to impart

If you need further information or help in making these changes feel free to reach out and I'll try to help.

[kenyon]

This will be fixed in #235, which we could use help with.

[ekohl]

Resolved in 4fad787#diff-12e598daecade60b04e493f45c134fec9287ac7471114d95d1995b4fb651a6c8