LOGSTASH-805
Merge branch 'master' into aws-iam-roles
Managed to hack together something that works (idk about docs though)
Merge branch 'master' into aws-iam-roles
removed unnecessary docgen code added earlier
put docgen code back in, fixed region & ssl configs
applied AwsConfig mixin to all AWS plugins
Merge branch 'master' into aws-iam-roles
added old config options for backward compatibility with deprecation warnings & info
added conditional around compatibility code
added a missing deprecated flag
moved call to setup_aws_config to mixin
Merge branch 'master' into aws-iam-roles
Merge pull request #307 from semiosis/aws-iam-roles

Common AWS plugin configuration mixin, supporting IAM Roles, YAML, &c (LOGSTASH-805)