chore: Add GitHub Settings (#224)

Author: osterman

.github/settings.yml

@@ -0,0 +1,7 @@
+# Upstream changes from _extends are only recognized when modifications are made to this file in the default branch.
+_extends: .github
+repository:
+  name: terraform-aws-elasticache-redis
+  description: Terraform module to provision an ElastiCache Redis Cluster
+  homepage: https://cloudposse.com/accelerate
+  topics: terraform, terraform-module, elasticache, aws, cache, elasticache-redis