Configured yard to use rdiscount instead of redcarpet.
Removed static API documentation from client classes.
Minor yard doc tag fix.
Moved Client class API documentation into yaml files inside doc-src.

These are now applied to the client classes as well as the parent Client
class.
Removed the no-longer-needed DynamoDB::ClientBase class.
Replaces @api private with @deprecated for AWS::DynamoDB::ClientV2.
Fixed faultly formatting of api docs.
Updated SWF and SNS api configurations.
Moved API doc src from client classes into YAML files.