Rewrote AWS Terraform for Kargo

Rewrote AWS Terraform deployment for AWS Kargo. It supports now
multiple Availability Zones, AWS Loadbalancer for Kubernetes API,
Bastion Host, ...

For more information see README

contrib/terraform/aws/modules/elb/main.tf

@@ -0,0 +1,50 @@
+resource "aws_security_group" "aws-elb" {
+    name = "kubernetes-${var.aws_cluster_name}-securitygroup-elb"
+    vpc_id = "${var.aws_vpc_id}"
+
+    tags {
+        Name = "kubernetes-${var.aws_cluster_name}-securitygroup-elb"
+    }
+}
+
+
+resource "aws_security_group_rule" "aws-allow-api-access" {
+    type = "ingress"
+    from_port = "${var.aws_elb_api_port}"
+    to_port = "${var.k8s_secure_api_port}"
+    protocol = "TCP"
+    cidr_blocks = ["0.0.0.0/0"]
+    security_group_id = "${aws_security_group.aws-elb.id}"
+}
+
+
+# Create a new AWS ELB for K8S API
+resource "aws_elb" "aws-elb-api" {
+  name = "kubernetes-elb-${var.aws_cluster_name}"
+  subnets = ["${var.aws_subnet_ids_public}"]
+  security_groups = ["${aws_security_group.aws-elb.id}"]
+
+  listener {
+    instance_port = "${var.k8s_secure_api_port}"
+    instance_protocol = "tcp"
+    lb_port = "${var.aws_elb_api_port}"
+    lb_protocol = "tcp"
+  }
+
+  health_check {
+    healthy_threshold = 2
+    unhealthy_threshold = 2
+    timeout = 3
+    target = "HTTP:8080/"
+    interval = 30
+  }
+
+  cross_zone_load_balancing = true
+  idle_timeout = 400
+  connection_draining = true
+  connection_draining_timeout = 400
+
+  tags {
+    Name = "kubernetes-${var.aws_cluster_name}-elb-api"
+  }
+}

contrib/terraform/aws/modules/elb/outputs.tf

@@ -0,0 +1,7 @@
+output "aws_elb_api_id" {
+    value = "${aws_elb.aws-elb-api.id}"
+}
+
+output "aws_elb_api_fqdn" {
+    value = "${aws_elb.aws-elb-api.dns_name}"
+}

contrib/terraform/aws/modules/elb/variables.tf

@@ -0,0 +1,28 @@
+variable "aws_cluster_name" {
+    description = "Name of Cluster"
+}
+
+variable "aws_vpc_id" {
+    description = "AWS VPC ID"
+}
+
+variable "aws_elb_api_port" {
+    description = "Port for AWS ELB"
+}
+
+variable "k8s_secure_api_port" {
+    description = "Secure Port of K8S API Server"
+}
+
+
+
+variable "aws_avail_zones" {
+    description = "Availability Zones Used"
+    type = "list"
+}
+
+
+variable "aws_subnet_ids_public" {
+    description = "IDs of Public Subnets"
+    type = "list"
+}