Azure/ubuntu/saltstack support re-instated

This first reverts commit 8e8437dad8.
Also resolves conflicts with docs on f334fc41
And resolves conflicts with https://github.com/kubernetes/kubernetes/pull/22231/commits
to make people switching between two different methods of setting up by
setting env variables.

Conflicts:
	cluster/get-kube.sh
	cluster/saltbase/salt/README.md
	cluster/saltbase/salt/kube-proxy/default
	cluster/saltbase/salt/top.sls

cluster/azure-legacy/config-default.sh

@@ -0,0 +1,58 @@
+#!/bin/bash
+
+# Copyright 2014 The Kubernetes 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.
+
+INSTANCE_PREFIX=kubernetes
+AZ_LOCATION='West US'
+TAG=testing
+AZ_CS_PREFIX=kube
+AZ_VNET=MyVnet
+AZ_SUBNET=Subnet-1
+AZ_IMAGE=b39f27a8b8c64d52b05eac6a62ebad85__Ubuntu-14_04_1-LTS-amd64-server-20140927-en-us-30GB
+AZ_CS="" # is set in azure/util.sh verify-prereqs
+
+AZ_SSH_KEY=$HOME/.ssh/azure_rsa
+AZ_SSH_CERT=$HOME/.ssh/azure.pem
+
+NUM_MINIONS=4
+
+MASTER_NAME="${INSTANCE_PREFIX}-master"
+MASTER_TAG="${INSTANCE_PREFIX}-master"
+MINION_TAG="${INSTANCE_PREFIX}-minion"
+MINION_NAMES=($(eval echo ${INSTANCE_PREFIX}-minion-{1..${NUM_MINIONS}}))
+MINION_IP_RANGES=($(eval echo "10.244.{1..${NUM_MINIONS}}.0/24"))
+MINION_SCOPES=""
+
+SERVICE_CLUSTER_IP_RANGE="10.250.0.0/16"  # formerly PORTAL_NET
+
+# Optional: Install node logging
+ENABLE_NODE_LOGGING=false
+LOGGING_DESTINATION=elasticsearch # options: elasticsearch, gcp
+
+# Optional: When set to true, Elasticsearch and Kibana will be setup as part of the cluster bring up.
+ENABLE_CLUSTER_LOGGING=false
+ELASTICSEARCH_LOGGING_REPLICAS=1
+
+# Optional: Cluster monitoring to setup as part of the cluster bring up:
+#   none     - No cluster monitoring setup 
+#   influxdb - Heapster, InfluxDB, and Grafana 
+#   google   - Heapster, Google Cloud Monitoring, and Google Cloud Logging
+ENABLE_CLUSTER_MONITORING="${KUBE_ENABLE_CLUSTER_MONITORING:-influxdb}"
+
+# Optional: Install Kubernetes UI
+ENABLE_CLUSTER_UI="${KUBE_ENABLE_CLUSTER_UI:-true}"
+
+# Admission Controllers to invoke prior to persisting objects in cluster
+ADMISSION_CONTROL=NamespaceLifecycle,LimitRanger,SecurityContextDeny,ServiceAccount,ResourceQuota