Add support for CircleCI (#20)

Execute a Terraform formatting check via CircleCI.

Author: hectcastro

.circleci/config.yml

@@ -0,0 +1,15 @@
+version: 2
+
+jobs:
+  build:
+    docker:
+      - image: hashicorp/terraform:latest
+
+    steps:
+      - checkout
+      - run:
+          name: Install Bash
+          command: apk add --no-cache bash
+      - run:
+          name: Execute cibuild
+          command: ./scripts/cibuild

LICENSE

@@ -187,7 +187,7 @@
       same "printed page" as the copyright notice for easier
       identification within third-party archives.
 
-   Copyright 2015 Azavea Inc.
+   Copyright 2019 Azavea Inc.
 
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.

README.md

@@ -1,5 +1,7 @@
 # terraform-aws-redis-elasticache
 
+[![CircleCI](https://circleci.com/gh/azavea/terraform-aws-redis-elasticache.svg?style=svg)](https://circleci.com/gh/azavea/terraform-aws-redis-elasticache)
+
 A Terraform module to create an Amazon Web Services (AWS) Redis ElastiCache cluster.
 
 ## Usage

scripts/cibuild

@@ -0,0 +1,22 @@
+#!/bin/bash
+
+set -e
+
+if [[ -n "${CI_DEBUG}" ]]; then
+    set -x
+fi
+
+function usage() {
+    echo -n \
+    "Usage: $(basename "$0")
+Ensure the Terraform source code is properly formatted.
+"
+}
+
+if [ "${BASH_SOURCE[0]}" = "${0}" ]; then
+    if [ "${1:-}" = "--help" ]; then
+        usage
+    else
+        terraform fmt -check
+    fi
+fi