[WFCORE-220] Set system properties in the CLI entry point

The original two PR's, #249 and #260, did this from the scripts. It's difficult to ensure that scripts parse the parameters correctly. This PR reverts the original two and sets the system properties in the CLI entry point. @aloubyansky needs to approve this.
The problem with scripts is parsing incoming parameters. If the `-Djboss.cli.config=path` wasn't expected to work as a parameter but as a `JAVA_OPTS` then it wouldn't be an issue. The more you can process in Java the better.

Windows batch scripts strip out the `=` when parsing them. So when you try to do something like `jboss-cli.bat -c --command=:shutdown` what gets passed as parameters to the CLI entry point is `-c`, `--command`, `:shutdown`. The equals is stripped.

The other option would be to change nothing and ensure we document that `jboss.cli.config` needs to be set as a `JAVA_OPTS`.