roguec: Improve help
roguec: Improve help

* Show default targets
* List cpp thread mode in initial list
* More info about --threads
* Improve and fix typo for --todo

Plasmaworks/Rogue,Plasmaworks/Rogue,Plasmaworks/Rogue,AbePralle/Rogue,AbePralle/Rogue,Plasmaworks/Rogue