Handle rate limiting errors

[iconara]

I think AWS rate limits on an account basis, so it's sometimes very easy to run into rate limiting errors.

Here's an example (unfortunately it didn't print the class name of the error):

Rate exceeded
	path/to/cuffsert/vendor/bundle/ruby/2.0.0/gems/aws-sdk-core-2.6.42/lib/seahorse/client/plugins/raise_response_errors.rb:15:in `call'
	path/to/cuffsert/vendor/bundle/ruby/2.0.0/gems/aws-sdk-core-2.6.42/lib/aws-sdk-core/plugins/idempotency_token.rb:18:in `call'
	path/to/cuffsert/vendor/bundle/ruby/2.0.0/gems/aws-sdk-core-2.6.42/lib/aws-sdk-core/plugins/param_converter.rb:20:in `call'
	path/to/cuffsert/vendor/bundle/ruby/2.0.0/gems/aws-sdk-core-2.6.42/lib/aws-sdk-core/plugins/response_paging.rb:26:in `call'
	path/to/cuffsert/vendor/bundle/ruby/2.0.0/gems/aws-sdk-core-2.6.42/lib/seahorse/client/plugins/response_target.rb:21:in `call'
	path/to/cuffsert/vendor/bundle/ruby/2.0.0/gems/aws-sdk-core-2.6.42/lib/seahorse/client/request.rb:70:in `send_request'
	path/to/cuffsert/vendor/bundle/ruby/2.0.0/gems/aws-sdk-core-2.6.42/lib/seahorse/client/base.rb:207:in `block (2 levels) in define_operation_methods'
	path/to/cuffsert/lib/cuffsert/rxcfclient.rb:87:in `block in stack_events'
	…

[bittrance]

According to aws/aws-sdk-ruby#705 there is a Seahorse retrying plugin installed, but it might be a bit timid. Suggests:

cf = Aws::CloudFormation::Resource.new({
  retry_limit: 10,
  retry_backoff: Proc.new { |attemps| sleep(2 ** attempts) }
})

Default retry_limit is 3 and calculated with Kernel.sleep(2 ** c.retries * 0.3) } so too short to be useful for throttling use cases.

In order to verify this, request logging is needed. According to https://aws.amazon.com/blogs/developer/logging-requests/ logging can be turned on thus:

require 'logger'
AWS.config(:logger => Logger.new($stdout))

Will give it a try to see if it makes any difference.