Update CHANGELOG.md

Author: rosbo

CHANGELOG.md

@@ -8,6 +8,7 @@ FEATURES:
 * **New Resource:** `google_project_iam_binding` - allows fine-grained control of a project's IAM policy, controlling only a single binding. [GH-171]
 * **New Resource:** `google_project_iam_member` - allows fine-grained control of a project's IAM policy, controlling only a single member in a binding. [GH-171]
 * **New Resource:** `google_compute_network_peering` ([#259](https://github.com/terraform-providers/terraform-provider-google/issues/259))
+* **New Resource:** `google_sourcerepo_repository` - allows creating and deleting Google Source Repositories [GH-256]
 
 IMPROVEMENTS:
 * compute: Add import support for `google_compute_subnetwork` ([#227](https://github.com/terraform-providers/terraform-provider-google/issues/227))