Make the classes pass most of the puppet-lint checks

I've done a basic puppet-lint --with-filename *.pp run and a tidy up of the issues it raises. If you don't have an explicit set of local puppet coding styles then the puppet-lint ones (which are derived from the Puppetlabs wiki) are a handy common set of short cuts to ensure the codebase stays consistent.

This also changes tabs to spaces so it might be even more contentious. I have no issues with this not being applied, I just wanted to show one of the options.