GitLab

exec java in docker entrypoint so java is pid 1
having java be pid 1 allows for stack dump via:
  docker kill --signal=QUIT cas

put docker image in gradle.propertiees so non-slim can be used if tools
like jstack are desired

Add gencert option to build.sh
Update help in build.sh

This also makes it easier to turn off console logging by only defining
it in the root appender.

There are some differences, like org.apache level was set to warn
instead of error, lots of things live under org.apache and it would be
better to adjust them individually rather than turn off warn messages
for all of them.