Updates the IAM Group Policy and IAM User Policy acceptance tests with random integer seeds.
Currently acceptance tests for these two resources are failing from leaked resources, adding distint naming should allow tests to pass regardless of parallel tests being ran or any resource leaks.
```
$ make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSIAMUserPolicy'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/22 00:19:13 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSIAMUserPolicy -timeout 120m
=== RUN TestAccAWSIAMUserPolicy_basic
--- PASS: TestAccAWSIAMUserPolicy_basic (22.54s)
=== RUN TestAccAWSIAMUserPolicy_namePrefix
--- PASS: TestAccAWSIAMUserPolicy_namePrefix (12.49s)
=== RUN TestAccAWSIAMUserPolicy_generatedName
--- PASS: TestAccAWSIAMUserPolicy_generatedName (13.13s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 48.191s
```
```
$ make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSIAMGroupPolicy'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/22 00:24:08 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSIAMGroupPolicy -timeout 120m
=== RUN TestAccAWSIAMGroupPolicy_basic
--- PASS: TestAccAWSIAMGroupPolicy_basic (23.89s)
=== RUN TestAccAWSIAMGroupPolicy_namePrefix
--- PASS: TestAccAWSIAMGroupPolicy_namePrefix (12.07s)
=== RUN TestAccAWSIAMGroupPolicy_generatedName
--- PASS: TestAccAWSIAMGroupPolicy_generatedName (13.15s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 49.140s
```