- change `validateResolveImageFlag()` to only perform _validation_,
and not combine it with modifying the option.
- use a `switch` instead of `if` in `validateResolveImageFlag()`
- `deployServices()`: break up some `switch` cases to make them
easier to read/understand the logic.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>