[Console] make InputArgument::setDefault() chainable

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | maybe
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | 
| License       | MIT

To allow chaining of methods, setDefault should return the InputArgument. I'm not quite sure if you would tread this as a BC break?

best regards
Philipp