Add types for EKS addon configuration

[flostadler]

EKS offers pre-packaged operational software like coredns or vpc-cni in the form of so called addons (see AWS docs).
All available addons are exposed by the generic resource aws.eks.Addon that takes a string with the json encoded configuration.

Having no type support for this means users have to frequently go back and forth between the AWS addon docs and look up potential options in the addon's json schema (can be retrieved with aws eks describe-addon-configuration). If an unknown/unsupported configuration value is passed, the change will fail during deploy time, causing longer dev cycles.

Offering types for the addons would significantly improve the user experience. Errors would be caught at preview time (or even during development for strongly typed languages). It's also easier to explore the available options in the Pulumi Registry and with auto complete.

From a technical perspective we already have the ability to generate pulumi types from jsonschema; that's being done in https://github.com/pulumi/pulumi-aws-native. The challenge that needs to be solved is coming up with a proper versioning strategy (forwards & backwards compatibility) and creating automation for generating the types.

Your feedback helps the Pulumi team prioritize, please upvote this issue if you're interested in having type support for EKS addons.