Live AWS parameter resolution and generics support

[drmmarsunited]

@rubenfonseca I have a hard fork of GoFormation that I have been using to build out a couple new features for my own use cases, being:

• Live parameter resolution with AWS account context (attempt to connect to an account to resolve data, otherwise return dummy placeholder data)
• Implementation of Go generics to alleviate typing issues (CloudFormation service tends to take in data and work whether it conforms to proper schema or not, for example, it will take a string for an integer value and vice versa, same with bools, etc)

Is there any interest on your part in trying to port these back into trunk? If so, I would love to keep doing the work to contribute the changes, otherwise I'm happy to just keep them on my fork.

[xrn]

@drmmarsunited I think would be great if you can open PR per feature - if you have any proposition how to improve this library