Greatly simplified the Seahorse::Model classes, removing
AWS logic from how they are defined. This has been moved
into `Aws::Model::Builder` which is responsible from
loading a JSON defenition and converting it into
an api, operations and shapes.

Also removed the need for the API to hold onto its JSON definition
and the number of objects generated.

No longer keeping protocol specific traits on shapes. These
now live in the new metadata for shapes and shape refs.

Query protocol clients now work as expected.

Previously, only white-listed traits were applied to the metadata
for the shapes and shape refs. Now all traits in the source
API will be applied. Non-modeled traits are treated as metadata.

Changes include:

* Corrected some bugs in the protocol tests where payload traits
  were applied in the wrong place.

* Shape and ShapeRef metadata now provides indifferent symbol and
  string access.

* Api#operation_names are now always symbols.

A number of traits were applied incorrectly.

Closes #792

Every client now generates and names all of its structure types.

The Client class operations and their input/output types
are now documented using Ruby structure classes. This eliminates
the deeply nested input & output tabs of the docs.

Work is still required to translate these to the resource operations
and to deal with documenting input structures as accepting hashes.

Moved the `# required` comment from the line before to the trailing
end of the line for required parameters.

Instead of giving a large pipe-delimited string, it now uses
the first value with a comment showing the full list of
accepted values.

Credential classes with refreshable credentials, such as
`Aws::InstanceProfileCredentials` and `Aws::AssumeRoleCredentials`
could return credential values such as `#access_key_id` and then
refresh before the paired `#secret_access_key` was returned.

This commit changes the primary interface for all credential providers
to have a single `#credentials` method that returns the tuple of
credentials in a single instance of `Aws::Credentials`. The request
signers now use this new method.

The following methods will be deprecated in 2.1.0 and eventually
removed in 2.2.0. They are implementation details and not public
methods. Until their removal, they will generate deprecation warnings.

* `#access_key_id`
* `#secret_access_key`
* `#session_token`

Previously, every single response returned became an instance of
`Aws::PageableResponse`. This caused confusion when the response
was not actually pageable. Instead now, the SDK will only decorate
responses with a pageable response mixin and will only do so
when the response might actually be pageable.

This also provides instant feedback when you attempt to enumerate a
response that can never be paged.

The constructor will now appear at the top of the page, before
the massive list of API operations for clients.

Changes include:

* Added a link to the constructor options from the top-level
  client example.
* Cleared up some of the language for default region and credentials.
* Added a link to information about the shared credentials file.

The gemspec was incorrectly including the doc files.

Resolved an issue where structure parameter values, such as those
returned in responses, could not be serialized as input parameters
when parameter conversion is disabled.

This fix resolves the issue by changing the serializes to all enumerate
structure/hash values in a consistent manor, using #each_pair. Also
added a few minor helpers to `Aws::Structure` making it quack more
like a Hash object.

Fixes #815

The request syntax examples have been improved and now have tests.
Also added response syntax examples with test.

API Structure types used as input now feature document
on their structure as a vanilla Hash on their class page.

Now sourcing the options tags from the called client methods
for the resource actions, filtering out the provided params.

Also DRY'd up some of the shared doc logic.

Also improved formatting of documenting input payloads for
streaming operations to reflect that you can pass an IO object
such as an opened file.

Conflicts:
	aws-sdk-core/lib/aws-sdk-core/api/customizer.rb
	aws-sdk-core/lib/seahorse/model/shapes.rb

These now share docstring logic with the client type structures,
allowing them to link to nested types.

The examples are kept as markdown files at the following
locations:

    examples/SVC/client/OPERATION/EXAMPLE_NAME.md

Conflicts:
	aws-sdk-core/lib/seahorse/client/plugins/restful_bindings.rb

The AWS protocols no longer reply on the restful bindings
plugin or the logic of the endpoint plugin. These have been
replaced by logic in the `Aws::Rest` module.

Conflicts:
	aws-sdk-resources/lib/aws-sdk-resources/documenter/base_operation_documenter.rb
	aws-sdk-resources/lib/aws-sdk-resources/documenter/data_operation_documenter.rb
	aws-sdk-resources/lib/aws-sdk-resources/documenter/operation_documenter.rb

Conflicts:
	aws-sdk-core/lib/aws-sdk-core/client.rb
	aws-sdk-core/spec/aws/client_spec.rb

Fixes #770

Fixes #804

Also, structure types are no longer converted.