change default aws linux instance type to t3.micro, reduce default template TTL (#2776)

- make default template max TTL 24 hours (still less than 168)
- make default workspace autostop 2 hours unless specified otherwise
- add instance type selector to aws templates

examples/templates/aws-linux/main.tf

@@ -36,6 +36,22 @@ variable "region" {
   }
 }
 
+variable "instance_type" {
+  description = "What instance type should your workspace use?"
+  default     = "t3.micro"
+  validation {
+    condition = contains([
+      "t3.micro",
+      "t3.small",
+      "t3.medium",
+      "t3.large",
+      "t3.xlarge",
+      "t3.2xlarge",
+    ], var.instance_type)
+    error_message = "Invalid instance type!"
+  }
+}
+
 provider "aws" {
   region = var.region
 }
@@ -130,7 +146,7 @@ EOT
 resource "aws_instance" "dev" {
   ami               = data.aws_ami.ubuntu.id
   availability_zone = "${var.region}a"
-  instance_type     = "t3.xlarge"
+  instance_type     = "${var.instance_type}"
 
   user_data = data.coder_workspace.me.transition == "start" ? local.user_data_start : local.user_data_end
   tags = {

examples/templates/aws-windows/main.tf

@@ -36,6 +36,22 @@ variable "region" {
   }
 }
 
+variable "instance_type" {
+  description = "What instance type should your workspace use?"
+  default     = "t3.micro"
+  validation {
+    condition = contains([
+      "t3.micro",
+      "t3.small",
+      "t3.medium",
+      "t3.large",
+      "t3.xlarge",
+      "t3.2xlarge",
+    ], var.instance_type)
+    error_message = "Invalid instance type!"
+  }
+}
+
 provider "aws" {
   region = var.region
 }
@@ -83,7 +99,7 @@ EOT
 resource "aws_instance" "dev" {
   ami               = data.aws_ami.windows.id
   availability_zone = "${var.region}a"
-  instance_type     = "t3.micro"
+  instance_type     = "${var.instance_type}"
   count             = 1
 
   user_data = data.coder_workspace.me.transition == "start" ? local.user_data_start : local.user_data_end