A new -shutdown <time> option has been created to specify the time when the client will stop asking for new jobs, will finish uploading the frames in the upload queue and will shutdown the computer. The time argument can have two different formats: an absolute date & time in the format yyyy-MM-ddThh:mm:ss (24h format) or a relative time in the format +m where m is the number of minutes from now.
The user can also select the shutdown-mode, where "wait" will wait for all the processes (render + pending uploads) to finish and "hard" will cancel all the pending jobs and will initiate the computer shutdown.
* We don't need to shadow in `lombok` itself. Gradle must be upgraded to at least 4.6 to support `annotationProcessor`, which is a version that still supports Java 7.
* `args4j-maven-plugin` is intended to use as a maven plugin.
* The requirement for `jaxb-api` was removed in 81cba7d58c0ce8a334204700dca669f2ad8e16ff
* We are only using `simple-xml`, don't need the whole `retrofit`+`okhttp`+`okio` chain.
* Resolve deprecation warnings in JNA code.
