Cfn-lint

Features
- Update rule [E3020](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E3020) to support CAA and CNAME record checks
- Update specs to ones released on August 16, 2018

Features
- Load all instances of CloudFormationLintRule in a file. Class doesn't need to match the filename anymore
- Allow load yaml to accept a string allowing people to use cfn-lint as a module
- Add rule [W6001](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#W6001) to test outputs that are just using an import value
- Update specs to ones released on August 10, 2018
Fixes
- Update [E2507](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E2507) to support conditions and using get_values to test all condition paths
- Update [E2521](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E2521), [E2523](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E2523) to support conditions and using get_values to test all condition paths
- Rewrite [E2503](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E2503) to support intrinsic functions and conditions and lower case protocols
- Fix [E1018](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E1018) to support Sub inside a Split function
- Fix [E3003](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E3003) description messages to be more informative
- Fix [E3001](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E3001) to not require parameters when CreationPolicy is used
- Fix SAM region when no region is available from a local AWS profile or environment variable.

Features
- Update rule [E3020](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E3020) to support AAAA record checks
Fixes
- Fix many rules that would fail if a sub parameter had a space at the beginning or end
- Fix crashing issues when trying to get resources that aren't properly configured

Features
- Update CloudFormation Specs to July 20th, 2018
Fixes
- Fix an issue with Exclusive resource properties and RDS with Snapshot and Password

Features
- Update CloudFormation specs to July 16th, 2018
- Support comma lists for regions, append rules, and ignore check parameters
- Added documentation explaining Resource Specification based rules
Fixes
- Fix a bunch of typos across many different rules
- Support DeepCopy with Template and custom String classes used for marking up templates
- Fix Rule [E3002](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E3002) to support CommaDelimitedList when looking for List Parameters
- Fix core engine to check that something is a Dict instead of assuming it is

Features
- Update CloudFormation Specs to July 12th, 2018
- Rule [E7012](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E7012) added to check the limits of attributes in a Mapping
- Rule [E2012](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E2012) added to check maximum size of a parameter value
- Rule [E1003](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E1003) added to check the maximum length of the template Description
- Guide created to help new users write new rules
Fixes
- Catch KeyError when trying to discover the line and column number of an error
- Update Lambda rules to support dotnet core
- Fix rule [E1017](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E1017) so we unpack first element of select as a dict
- Fix rule [E1024](https://github.com/aws-cloudformation/cfn-python-lint/blob/main/docs/rules.md#E1024) to support ImportValue and appropriately checking number for the last element