Introduce params.pp
Rename template diamond.conf to diamond.conf.erb
Use inheritance to make module variables (of parameterized class)
available, follows Puppet style guide
Default undefined string vars to undef, use @var syntax in template
Add more class parameters to facilitate Hiera-based deployments
Drop Puppet 2.7 support and testing
Add testing for Ruby 2.0.0
Use stdlib to perform class parameter input validation
Use full var scope to make lint happy
Quote strings