Code Style / Initial IDE Configuration

Additional configuration of IntelliJ for contributors (and committers).

Prepare for Build

The project/artifact isis-core-privileged is required to be an automatic module in the Java Platform Module System (JPMS) sense. (It has unrestricted access to the class-path but not the module-path.)

As of time of writing, IntelliJ IDEA does not support automatic module name resolution for projects that are also opened in the IDE. Instead it will resolve such module names only from ignored projects, that previously had been built and installed via Maven to the local repository. (Typically ~/.m2/repository).