Move terraform and kubernetes folder to be under proxy (#127)

* Move terraform and kubernetes folder to be under proxy

There is no reason for them to be under proxy/src/... any more now that
we have a Gradle-idiomatic folder structure.

proxy/terraform/modules/networking/variables.tf

@@ -0,0 +1,20 @@
+# Instance groups that the load balancer forwards traffic to.
+variable "proxy_instance_groups" {
+  type = "map"
+}
+
+# Suffix (such as "-canary") added to the resource names.
+variable "suffix" {
+  default = ""
+}
+
+# Node ports exposed by the proxy.
+variable "proxy_ports" {
+  type = "map"
+}
+
+# DNS zone for the proxy domain.
+variable "proxy_domain" {}
+
+# domain name of the zone.
+variable "proxy_domain_name" {}