Make "Internal Failure" errors more explicit

## Make "Internal Failure" errors more explicit

## 2. Scope of request

When performing CloudFormation operations, the stacks sometimes fail with the error message *Internal Failure*. This can have multiple reasons like internal parsing failures, service disruptions etc. For me as a developer, it is hard to track the root cause and usually I will open a support ticket and often get help but I always need to wait.

## 3. Expected behavior

From a UX perspective, the error is not helpful so I would be so happy when the message could be more detailed, even if the client error is something like *Failed to parse template* or *Failed to connect to downstream service IAM*.

## 4. Suggest specific test cases

## 5. Helpful Links to speed up research and evaluation

Here is an example:


## 6. Category (required) - Will help with tagging and be easier to find by other users to +1

UX