us-east-1
Fixes#11175
Because of a previous limitation that codecommit only ran in us-east-1,
we hard coded the session under which it should run. This has caused the
repository to be spun up in the wrong region regardless of what region
was passed to the provider
```
make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSCodeCommitRepository_'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/01/12 16:09:52 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSCodeCommitRepository_ -timeout 120m
=== RUN TestAccAWSCodeCommitRepository_basic
--- PASS: TestAccAWSCodeCommitRepository_basic (23.28s)
=== RUN TestAccAWSCodeCommitRepository_withChanges
--- PASS: TestAccAWSCodeCommitRepository_withChanges (33.71s)
=== RUN TestAccAWSCodeCommitRepository_create_default_branch
--- PASS: TestAccAWSCodeCommitRepository_create_default_branch (22.70s)
=== RUN TestAccAWSCodeCommitRepository_create_and_update_default_branch
--- PASS: TestAccAWSCodeCommitRepository_create_and_update_default_branch (32.72s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 112.437s
```
The provider should, when working on a new repository without branches:
* Able to create a new repository even with default_branch defined.
* Able to create a new repository without default_branch, and do not fail
if default_branch is defined.