Bump version to 1.8.5
Added documentation for for AWS::CloudWatch::Client operations.
Added a rule to ignore enum traits.
Resolved an issue with the OpsWorks API configuration.

One of the input params was incorrectly inflected.
Added valid values to the documentation for each service client.
Added #vpc_id and #vpc methods to AWS::RDS::DbInstance.

Fixes #188
Now using us-west-2 as the default sample region for documentation.
Corrected typo in SQS::Queue documentation.
parameters was not being passed
Merge pull request #203 from patcheng/fix_cloudformation_estimate_template_cost

estimate_template_cost was not working for template that as parameters
Update CloudFormation specs to reflect new API
Only load config file if it exists
Resolved a thready-safety issue with AWS::Core::Configuration.

References #90
No longer catching all 400-level errors when calling Bucket#exists?

Fixes #205
Added additional header (expires) returned by AWS::S3::Client#head_object and #get_object
add to_s method, because Rails.version of edge rails is Gem::Version object
Merge pull request #208 from tsukasaoishi/check_rails4_version

add to_s method, because Rails.version of edge rails is Gem::Version obj...
Merge pull request #206 from ebargtuo/s3-client-expires-header

Added additional header (expires) returned by AWS::S3::Client#head_object and #get_object