Introduce ShellContext.getCommandLine()

See ticket for background
https://github.com/fabric8io/fabric8/issues/5586

We have noticed this happens when the addon command is using a wizard (steps). We have a command that depends on what Camel component you chose, has N+ steps with at most 20 options per step. The options is a mix between required=true or required=false options. However 98% is required=false.

What we have noticed is that if we provide all the nessasary information as arguments to the command, then no matter what, then forge turns on the interactive mode, and prompts the end users to select/enter values for all the options in the LAST step.