Add pessimistic constraint to puppet_forge dependency

[scotje]

At some point there will probably be a 2.x release of the puppet_forge gem that may not be backwards compatible. Pessimistic version constraints on dependencies is also a RubyGems best practice: http://guides.rubygems.org/patterns/#declaring-dependencies

[carlossg]

I'm more inclined to leave it as is and if that is the case in the future users can explicitly add the constraint themselves. I've seen too many cases where a constraint set early screws up downstream users that want to use a newer version

[scotje]

The proposed constraint allows everything < 2.0.0. In the current scenario, if we push a puppet_forge 2.x, anyone who has not independently constrained on puppet_forge 1.x is likely going to break their install the next time they gem update or bundle update.

If it turns out that existing versions of librarian-puppet are compatible with puppet_forge 2.x, it seems simple enough to publish a z-release with an expanded dependency range so people can upgrade.

Obviously it's up to you guys what you want to do. Consider this an early heads up that a 2.x puppet_forge is looking pretty likely at this point and it will almost certainly not be fully backwards compatible with the 1.x series.

[carlossg]

I misunderstood, if you already know that is not backwards compatible then it makes sense