Moonshot 1.0 tag changes cannot work with some resource types.

[Kyle Smith]

In particular, DBCluster tags can never be updated. We need to implement a config option for a tagging strategy so that stacks with these resources already launched in production can continue to use the same tagging strategy.

I would imagine it looks something like two classes called LegacyTaggingStrategy and TaggingStrategy. Each would be set in the ControllerConfig, defaulting to TaggingStrategy. The create, update and list actions would use the strategy to understand how to create, update and find resources, respectively.

# Example Moonfile.rb file using the legacy strategy
Moonshot.config do |c|
  c.tagging_strategy = Moonshot::LegacyTaggingStrategy.new
end

[Kyle Smith]

We should probably include a note in the 1.x cutover guide as well about why you might choose to use the legacy strategy.