update Dockerfile

Author: bingzhang

scripts/tester/Dockerfile

@@ -1,5 +1,15 @@
 FROM ubuntu:16.04
 
+
+# environemnt variables
+ENV CLOWDER_URL=${CLOWDER_URL} \
+    CLOWDER_KEY=${CLOWDER_KEY} \
+    TARGET_FILE=${TARGET_FILE} \
+    SLACK_TOKEN=${SLACK_TOKEN} \
+    SLACK_CHANNEL=${SLACK_CHANNEL} \
+    SLACK_USER=${SLACK_USER}
+
+
 RUN apt-get update && apt-get install -y curl jq && apt-get clean && rm -rf /var/lib/apt/lists
 
 COPY tester.sh /