Tidying up meta data

As title says, does not change functionality just updates meta data.
However, the dependency change might cause problems. Will test it later today.

- adding project reference for Eclipse
- removing checksums from metadata.json (new Puppet plugin does not create them any more)
- updating dependency: Puppet module concat (ripienaar/concat) is now puppetlabs-concat*

*https://github.com/puppetlabs/puppetlabs-concat