Style guide changes and testing

This work from slamont looks good to me... mostly it updates the manifests to comply with the puppet style guide (i.e. puppet-lint). He also adds some testing, which I haven't tested myself but looks good. I was about to do this myself before I found his fork.

BTW, very nice work on this module. I'm about to start a fairly large Icinga rollout at my day job with this as the base. I'll be doing some work on my fork as well, at this point mainly just adding puppetdoc headers to all of the manifests.