Add beaker tests, change init approach

This is a set of major changes:

- Remove dependency on camptocamp/ruby
- Switched to gem-based install by default
- Package-based install currently expected to be broken
- Add app-specific init scripts with status capability, to facilitate beaker testing
- Make app-specific init scripts default; thin service is no longer configured by default
- Add beaker tests that pass on debian 7. 
- Init scripts not expected to work on non-debian derived distros

I realize this is a major, backwards-incompatible change. I'm trying to tidy up the [puppet-puppet](https://github.com/puppetlabs-operations/puppet-puppet) module, and need a working thin module, so I'm making changes as needed toward that end. 

I'm not sure whether anybody is still maintaining this module, so I'll expect to run my own fork but am trying to contribute changes back upstream in case somebody is still using this. Please let me know if this breaks your use case and I'll try to update it so that it doesn't.