Release v2.0.0-preview.3 (2018-03-08) (aws#147)

Services
---
* Synced the V2 SDK with latests AWS service API definitions.

Breaking Changes
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* `private/mode/api`: Refactor service paginator helpers to iterator pattern (aws#119)
	* Refactors the generated service client paginators to be an iterator pattern. This pattern improves usability while removing the need for callbacks.
	* See the linked PR for an example.
* `private/model/api`: Removes setter helpers from service API types (aws#101)
	* Removes the setter helper methods from service API types. Removing clutter and noise from the API type's signature.
	* Based on feedback aws#81
* `aws`: Rename CanceledErrorCode to ErrCodeRequestCanceled (aws#131)
	* Renames CanceledErrorCode to correct naming scheme.

SDK Bugs
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* `internal/awsutil`: Fix DeepEqual to consider string alias type equal to string (aws#102)
	* Fixes SDK waiters not detecting the correct condition is met. aws#92
* `aws/external`: Fix EnvConfig misspelled container endpoint path getter (aws#106)
	* This caused the type to not satisfy the ContainerCredentialsEndpointPathProvider interface.
	* Fixes aws#105
* `service/s3/s3crypto`: Fix S3Crypto's handling of TagLen (aws#107)
	* Fixes the S3Crypto's handling of TagLen to only be set if present.
	* V2 Fix for aws/aws-sdk-go#1742
* `private/model/api`: Update SDK service client initialization documentation (aws#141)
	* Updates the SDK's service initialization doc template to reflect the v2 SDK's configuration update change from v1.
	* Related to aws#136

SDK Enhancements
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* `aws`: Improve pagination unit tests (aws#97)
	* V2 port of aws/aws-sdk-go#1733
* `aws/external`: Add example for shared config and static credential helper (aws#109)
	* Adds examples for the  config helpers; WithSharedConfigProfile, WithCredentialsValue, WithMFATokenFunc.
* `private/model/api`: Add validation to prevent collision of api defintions (aws#112)
	* V2 port of aws/aws-sdk-go#1758
* `aws/ec2metadata`: Add support for AWS_EC2_METADATA_DISABLED env var (aws#128)
	* When this environment variable is set. The SDK's EC2 Metadata Client will not attempt to make requests. All requests made with the EC2 Metadata Client will fail.
	* V2 port of aws/aws-sdk-go#1799
* Add code of conduct (aws#138)
* Update SDK README dep usage (aws#140)

Release v2.0.0-preview.2 (aws#95)

Release v2.0.0-preview.2 (2018-01-15)
===

### Services
* Synced the V2 SDK with latests AWS service API definitions.

### SDK Bugs
* `service/s3/s3manager`: Fix Upload Manger's UploadInput fields ([aws#89](aws#89))
	* Fixes [aws#88](aws#88)
* `aws`: Fix Pagination handling of empty string NextToken ([aws#94](aws#94))
	* Fixes [aws#84](aws#84)

Update Readme for preview release (aws#67)

Updates the SDK's README and version (`v2.0.0-preview.1`) for the preview release.