Module assumes grafana 2.5 but grafana says 4.1.2 is newest (on debian/ubuntu)

[JeffAbrahamson]

The grafana docs for installing on debian/ubuntu indicate that the current stable version of grafana is 4.1.2.

But puppet-grafana thinks the most recent should be 2.5.0. Even when setting manage_package_repo => false and version => '4.1.2', version 2.5.0 is installed.

[wyardley]

FYI, working on this in the Voxpupuli fork (welcome to cherry-pick those changes in here too, @bfraser).

voxpupuli#61