Provide mechanism for seeing what will change when a cluster or resource is inlocked

[gregswift]

Is your feature request related to a problem? Please describe.
Right now when you lock a cluster or resource, you don't have an easy way to determine what will change when you unlock it. In the puppet/chef world you would do a dry run and get a list of all the intended changed resources that you can review before doing a real run of their agents.

Describe the solution you'd like
In an ideal world we would run a command/API call and get a detailed output with a full list of resources and what specifically will change on the next run of the controllers. This would match puppet/chef behavior.

Describe alternatives you've considered
Talking with @alewitt2 it seems a doable version of this is to have the controllers continue to process things as usual, and but when a cluster or resource is locked the controller would just record that they "want" to change a resource instead of changing it. The end users could then take that list and look at the current resource and whatever is providing the newest resource and figure out the changes for themselves.

[gregswift]

I just had a very interesting idea. Why not update an annotation like deploy.razee.io/pending-application ?

Then when it is unlocked, and you apply, it gets removed.

That would be slick, and probably not require a whole new model and storage