Bump version to v2.0.0.rc8
Added support for transitioning versioned S3 objects to Glacier.
Added a missing :step to the handler list validation message.
Updates for the S3Md5 plugin.

Updates include:

* Disabled checksums on empty body.
* Now using OpenSSL::Digest::MD5 instead of Digest::MD5.
* Expanded test coverage.
* Clarified configuration option.
Expanded the query param seralization to include the trailing '=' when the value is nil.
Added basic support for presigned v4 urls.
Added support to Aws::EC2 copying encrypted snapshots.

Added support for the 2014-05-01 API version.  The SDK
will automatically compute the additional request params,
`:destination_region` and `:presigned_url` on your behalf.
Removed some development cruft.
Updates AWS APIs.
Fix NameError for `412Error` on 412 without body

>> Aws::S3.new.head_object(if_unmodified_since: '2014-06-09 12:44:21 +0900', bucket: '...', key: '...')
NameError: wrong constant name 412Error
Merge pull request #65 from sorah/fix-412error

Fix NameError for `412Error` on 412 without body
Added support for S3 serversSide-encryption with customer-provided keys.
Added integration for customer-provided sse keys.
Added support to Aws::SNS for publishing with message attributes.
Added support to Aws::Redshift for cluster identifiers.
Merge branch 'master' into normalized-resources

Conflicts:
	apis/DynamoDB-2012-08-10.json
	apis/ElasticBeanstalk-2010-12-01.json
	apis/OpsWorks-2013-02-18.json
	apis/Redshift-2012-12-01.json
	apis/S3-2006-03-01.json
	apis/SNS-2010-03-31.json
	apis/source/elasticbeanstalk-2010-12-01.json
	apis/source/opsworks-2013-02-18.json
	apis/source/redshift-2012-12-01.json
	apis/source/s3-2006-03-01.json
	apis/source/sns-2010-03-31.json
	lib/aws.rb
	lib/aws/api/service_translators/s3.rb
Bug fix for EC2 copy snapshot.
Merge branch 'master' into normalized-resources
Resource updates.
Glacier resource model fixes.