Add awsQueryCompatible error code translation support

[eddy-aws]

The awsQueryCompatible error code is returned if the error header is found in the response. This is a pre-requisite for migrating services from AWSQuery wire protocol to AWSJson. Detailed description of this change if AWSQueryCompatible trait is present:

• a new map queryException is created. This maps the error code to exception function that creates typed error with a given error code
• error structs are added a new code field
• the Code() function would return a non-empty code value, else returns the default value
• a typed error is created with query compatible error code and returned
• a generic error with query compatible error code is returned for an untyped error

A test service has been generated for validating assumptions. Added unit tests as per the SEP.

it appears that the existing PR will break customers