[Enhancement] Auto Rule Generation from CloudFormation Resource Specification

[dontirun]

Request:

Make rules to validate that a template defines resources that exist for a particular region using the CloudFormation resource specifications

Reason

I currently develop CDK/CloudFormation that need to work across across various regions. I would like to make sure that my templates do not define resources that don't exist in one of the regions I intend to deploy to

[PatMyron]

related to #9, this specific use-case is one of the purposes of cfn-lint:

cfn-lint -r us-west-2 currently flags regional unavailability of resource types and instance types

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Keeping this open since other use-cases like #86 (comment) would benefit from this

although we might prefer the newer Resource Schemas over the older Resource Specifications

[dontirun]

It would be nice to have some default rules in cfn-guard that relate to unsupported attributes to use with cfn-lint as well for a more complete checking experience

For example

1. I create a template meant for cross region deployments
2. Using cfn-lint, the resource specification and resource schemas can tell you that EC2 instances are supported in region X
3. With cfn-guard I can check if the M6g instance type that I specified for my instance is supported