* provider/aws: Add errcheck to Makefile, error on unchecked errors
* more exceptions
* updates for errcheck to pass
* reformat and spilt out the ignore statements
* narrow down ignores
* fix typo, only ignore Close and Write, instead of close or write
* provider/aws: add `aws_ssm_document` resource
* provider/aws: Changes to `aws_ssm_document` post code review
The changes are things like using d.Id rather than d.Get("name").(string)
and errwrap.Wrapf rather than fmt.Errorf