In order to ensure, we have the same experience across operating systems
and shells, this commit uses the java CLI parser instead of the shell
getopt parsing to parse arguments.
This also allows for support for paths, which contain spaces.
Also commons-cli depdency was upgraded to 1.3.1 and tests have been added.
Changes
* new exit code, OK_AND_EXIT, allowing to tell the caller to exit, as everything
went as expected (e.g. when running a version output)
BWC breaking:
* execute() returns an ExitStatus instead of an integer, otherwise there is no
possibility to signal by a command, if the JVM should be exited after a run.
This affects plugins, that have command line tools
* -v used to be version, but is a verbose flag by default in the current CLI infra,
must be -V or --version now
* -X has been removed - the current implementation was useless anyway, as
it prefixed those properties with "es.". You should use
ES_JAVA_OPTS/JAVA_OPTS for JVM configuration
