Add firehose elasticsearch configuration documentation
Adding CRUD for elastic search as firehose destination
Updated the firehose stream documentation to add elastic search as destination example.
Adding testing for es as firehose destination
Update the test case for es
* Added support for redshift destination to firehose delivery streams
* Small documentation fix
* go fmt after rebase
* small fixes after rebase
* provider/aws: Firehose test cleanups
* provider/aws: Update docs
* Convert Redshift and S3 blocks to TypeList
* provider/aws: Add migration for S3 Configuration in Kinesis firehose
* providers/aws: Safety first when building Redshift config options
* restore commented out log statements in the migration
* provider/aws: use MaxItems in schema
As I was fixing up the AccTests to not depend on a single existing IAM
role (which this commit does), I noticed that without some sleeping that
the kinesis_firehose_delivery_stream would often come back with:
```
msg: Firehose is unable to assume role {{arn}}. Please check the role provided.
code: InvalidArgumentException
```
Similar to the strategy taken in aws_instance with IAM Instance Profile errors,
I dropped in a simple retry loop which seemed to take care of the issue. Seems
that the same permission propagation delays apply here too.
Paul Stack