Rabix Executor feature request - grouping and required flags

[DavidAustinNix]

Hello Folks,

These are a few feature requests for the rabix executor. When executing without params the executor dumps out the params in alphebetical order. It would be better to order these using the indicated cmd line order and for workflows, group them by tool. Lastly it would be nice to know which are required and which are optional.

Thanks, David