Add CI-based build of rtmgr using multiple stages

Created single Dockerfile based on existing files.
Added tag-definition file that is read by the Jenkins job
that builds a Docker image.
Upgrade to go version 1.12.
Un-ignore and add .gitreview file.

Signed-off-by: Lott, Christopher (cl778h) <cl778h@att.com>
Change-Id: Ic1c15844a83b36e59bd94f8ea5c424e41177908d
diff --git a/Dockerfile b/Dockerfile
new file mode 100644
index 0000000..10cdd1c
--- /dev/null
+++ b/Dockerfile
@@ -0,0 +1,38 @@
+#==================================================================================
+#   Copyright (c) 2019 AT&T Intellectual Property.
+#   Copyright (c) 2019 Nokia
+#
+#   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.
+#==================================================================================
+
+# The CI system creates and publishes the rtmgr Docker image
+# from the last step in this multi-stage build and applies 
+# a Docker tag from the string in file container-tag.yaml
+
+FROM golang:1.12 as rtmgrbuild
+ENV GOPATH /opt
+RUN apt-get update \
+    && apt-get install golang-glide
+COPY . /opt
+RUN mkdir -p $GOPATH/bin \
+    && ln -s -f  $GOPATH/pkg $GOPATH/src \
+    && cd $GOPATH/src \
+    && glide install --strip-vendor \
+    && cd $GOPATH/cmd \
+    && go build rtmgr.go \
+    && mv $GOPATH/cmd/rtmgr $GOPATH/bin
+
+FROM ubuntu:16.04
+COPY --from=rtmgrbuild /opt/bin/rtmgr /
+RUN mkdir /db && touch /db/rt.json
+CMD /rtmgr