Add autoscaling policy and create ami_data module

modules/ami_data/main.tf

@@ -0,0 +1,20 @@
+data "aws_ami" "amazon_linux" {
+  most_recent = true
+
+  filter {
+    name   = "name"
+    values = ["amzn2-ami-*-gp2"]
+  }
+
+  filter {
+    name   = "architecture"
+    values = ["x86_64"]
+  }
+
+  filter {
+    name   = "virtualization-type"
+    values = ["hvm"]
+  }
+
+  owners = ["amazon"]
+}

modules/ami_data/outputs.tf

@@ -0,0 +1,3 @@
+output "amazon_linux" {
+  value = data.aws_ami.amazon_linux
+}