Hammer CLI

Adding some more info:

Reproducible with hammer-cli-katello, try:

hammer content-view -h

Warnings are printed from method `handles?(switch)` in OptionDefinition https://github.com/theforeman/hammer-cli/blob/master/lib/hammer_cli/options/option_definition.rb#L55
The method is called also when commands check for existence of options. It should be moved to `take(value)` of Argument::Instance https://github.com/mdub/clamp/blob/master/lib/clamp/attribute/instance.rb#L55 Hammer's OptionDefinition should provide it's own descendant of an argument instance with deprecation tweaks.