Add a Gradle task to deploy the proxy (#214)

Also refactored some common code regarding the mapping between
environments and projects.

The script to update proxy deployments and kill all pods are lifted from
https://cs.corp.google.com/piper///depot/google3/domain/registry/tools/bashrc?l=163

proxy/deploy-proxy-for-env.sh

@@ -0,0 +1,44 @@
+#!/bin/bash
+# Copyright 2019 The Nomulus Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# This script builds the GAE artifacts for a given environment, moves the
+# artifacts for all services to a designated location, and then creates a
+
+if [[ $# -ne 1 ]]; then
+ echo "Usage: $0 alpha|crash"
+ exit 1
+fi
+
+environment=${1}
+project="domain-registry-"${environment}
+current_context=$(kubectl config current-context)
+while read line
+do
+  parts=(${line})
+  echo "Updating cluster ${parts[0]} in zone ${parts[1]}..."
+  gcloud container clusters get-credentials "${parts[0]}" \
+    --project "${project}" --zone "${parts[1]}"
+  # Kills all running pods, new pods created will be pulling the new image.
+  sed s/GCP_PROJECT/${project}/g "./kubernetes/proxy-deployment-${environment}.yaml" | \
+  kubectl replace -f -
+  # Alpha does not have canary
+  if [[ ${environment} != "alpha" ]]
+  then
+  sed s/GCP_PROJECT/${project}/g "./kubernetes/proxy-deployment-${environment}-canary.yaml" | \
+  kubectl replace -f -
+  fi
+  kubectl delete pods --all
+done < <(gcloud container clusters list --project ${project} | grep proxy-cluster)
+kubectl config use-context "$current_context"