this has several advanges:
- a consistent and complete help message is now printed by passing the
-h or --help command line parameters. most notably this allows to
generically implement tab completion of parameters for bash
- the full list of runtime parameters can now be printed before the simulator
has been run.
- all runtime parameters understood by ebos can be specified
- no hacks to marry the two parameter systems anymore
- command parameters now follow the standard unix convention, i.e.,
`--param-name=value` instead of `param_name=value`
on the negative side, some parameters have been renamed and the syntax
has changed so calls to `flow` that specify parameters must adapted.
