Fixes an uncaught panic during an interface cast in the `template_cloudinit_config` data source.
Fixes: #13572
```
$ make test TEST=./builtin/providers/template TESTARGS="-v -run=TestRender_handlePanic"
==> Checking that code complies with gofmt requirements...
==> Checking AWS provider for unchecked errors...
==> NOTE: at this time we only look for uncheck errors in the AWS package
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/04/12 10:46:33 Generated command/internal_plugin_list.go
go test -i ./builtin/providers/template || exit 1
echo ./builtin/providers/template | \
xargs -t -n4 go test -v -run=TestRender_handlePanic -timeout=60s -parallel=4
go test -v -run=TestRender_handlePanic -timeout=60s -parallel=4 ./builtin/providers/template
=== RUN TestRender_handlePanic
--- PASS: TestRender_handlePanic (0.00s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/template 0.028s
```
When creating an `aws_route_table`, if a `route` configuration block is left `nil`, Terraform would previously panic. This allows Terraform to catch a faulty interface conversion during the resource create. The resource will still fail to apply, however, since every item in the `route` element is `Optional` we cannot currently catch this error during plan time, via validation.
Fixes: #13545
* Add schema_version as computed ssm document attribute
* Update the SSM document itself if the content has changed and it has a schema >= 2.0
* Add default_version as DocumentVersion in SSM doc update
* Acceptance test for updating an SSM document
* Better error handling in updating SSM documents
* Add SSM document update documentation
* Better names for SSM input params
Launch permissions are implicitly nuked if an AMI is removed for any
reason - Terraform should not error on refresh in this case, but rather
just see the launch permissions as gone and react appropriately.
The acctests depend on getting a particular result back from resolving
www.hashicorp.com, which seems to have changed. In the long run we should
probably *not* be depending on the DNS configuration of the main Hashicorp
website, but this is just a quick fix to get the build back to green so
we can continue work on other things.
* provider/aws: Fixed DynamoDB GSI update when using multiple indexes
* provider/aws: Fixed DynamoDB GSI set hash function
* Added DynamoDB table state migration
Jake Champlin