mv aws module to addons, adding example usage, adding readme with tfdocs

[magusd]

Solves:
#6 - partially, adds the concept of "addons" and a simple refactor of the aws module into a aws.bucket addon
#7 - adds example usage for the s3 module and an example usage of this module under examples/simpleapp

Example usage on examples/simpleapp/main.tf

addons = {
    media = {
      addon_type = "aws.bucket"
      config = {
        name = local.app_name
        username = local.app_name
        public = true
      }
    }
  }