Unified WAR deployment unit

We will create necessary adjustments to the build and docker tasks in order to use unified `shibui.war` deployment unit which could be used with embedded Tomcat container deployment model i.e. via `java -jar`, deployed to external Tomcat container or deployed as an embedded Tomcat model in Docker container. Furthermore, this could be configured to be deployed under any arbitrary servlet context root.

In the current model, `bootJar` and `bootWar` tasks are used to produce both jar and war deployment units, but with the recent change on the backend to accommodate deployment under any servlet context, the pure jar packaging does not work anymore as the implementation uses servlet context loader to get of of classpath resource file. Having jar and war units does not make sense and war deployment unit works fine to accommodate various supported deployment models