Adding tools to get image names from charts, pull images locally given a list, refactored tag and push.

Change-Id: I276e2b3f8093d39651f91d86245a80fb1563e0a8
diff --git a/developer/images_from_charts.sh b/developer/images_from_charts.sh
new file mode 100755
index 0000000..66e7bb2
--- /dev/null
+++ b/developer/images_from_charts.sh
@@ -0,0 +1,45 @@
+#!/usr/bin/env bash
+
+# Copyright 2018-present Open Networking Foundation
+#
+# 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.
+
+# copy-ssh-keys.sh - Adds ssh keys to nodes given as parameters to the script,
+# after removing them from the ~/.ssh/known_hosts file on the local system.
+#
+# This script should be run interactively as it will prompt for input, and only
+# invoked once, so as not to add multiple copies of the SSH key to the remote
+# system.
+
+#############################################################
+#                                                           #
+#    Returns a list of images given a list of helm charts   #
+#                                                           #
+#############################################################
+
+output=""
+for chart in "$@";
+do
+  if [ "${chart}" = "etcd-cluster" ]; then
+    # shellcheck disable=SC1117
+    output+=$(helm template "${chart}" | grep "busyboxImage:\|version:\|repository:" | sed 's/busyboxImage://g' | sed 's/version://g'| sed 's/repository://g' | sed -e 's/^[[:space:]]*//' -e 's/[[:space:]]*$//' | tr -d \" | awk '(NR%2){print$0p}{p=":"$0}')
+    # shellcheck disable=SC1117
+    output+="\n"
+  else
+    output+=$(helm template "${chart}" | grep "image:" | sed 's/image://g' | sed -e 's/^[[:space:]]*//' -e 's/[[:space:]]*$//' | tr -d \")
+    # shellcheck disable=SC1117
+    output+="\n"
+  fi
+done
+
+echo -e "${output}" | sort | uniq | sed '/^\s*$/d'