Modified dockerfile to do multistage build

Dockerfile

-FROM tomcat
-COPY build/draw.war  /usr/local/tomcat/webapps
+FROM frekele/ant:1.10.3-jdk8 as  BUILD
+RUN mkdir /usr/build
+COPY src /usr/build/src
+COPY etc /usr/build/etc
+COPY war /usr/build/war
+COPY VERSION /usr/build
+RUN cd /usr/build/etc/build/
+RUN ant -file /usr/build/etc/build/build.xml war
+
+FROM tomcat:9.0 as TARGET
+COPY --from=BUILD /usr/build/build/draw.war  /usr/local/tomcat/webapps/
 EXPOSE 8080
-CMD ["catalina.sh", "run"]
+CMD ["catalina.sh", "run"]
\ No newline at end of file

README.md

@@ -17,14 +17,6 @@ A development guide is being started on the GitHub project wiki. There is a [dra
 
 The [mxGraph documentation](https://jgraph.github.io/mxgraph/) provides a lot of the docs for the bottom part of the stack. There is an [mxgraph tag on SO](http://stackoverflow.com/questions/tagged/mxgraph).
 
-Building
---------
-From project directory,
-```bash
-cd etc/build/
-ant war
-```
-This will create a war under build directory.
 
 Docker
 ------