Fix lambda event source mapping typo and requrements

Thanks @justjohn2001 !

Add additional specs to SAM Functions

 Add specs to SAM functions  (#185)

Adds support for setting the `DeadLetterQueue` and `ReservedConcurrentExecutions` values for Serverless Functions

Updates to Serverless Function Specs

Updates to SAM function specs (#184)

* update serverless function name spec with length limit

* update serverless event source type spec with more options

Correct rds resource types

Thanks @AgentO3

Allow references in two Neptune DBCluster fields

Quick update to allow mixed vectors of strings and refs in the Neptune DBCluster

Fix ASG rolling-update/creation policy prop names

Thanks to @csumpter for this fix!

Bump tools.cli to 0.4.2

Minor version bump

EC2 Volumes

Support for AWS::EC2::Volume thanks to @AgentO3!

Instance Profiles

Thanks to @AgentO3 for this update!

Updates to CouldWatch and SNS

CloudWatch

• Correct ->key override for :ok-actions
• Change string types to correct data types

SNS

• Allow ::endpoint to be a reference