Fixes #6261 - add delete subcommand to AK

this adds the 'delete' subcommand to activation-key
Merge pull request #192 from dustint-rh/ak_delete

Fixes #6261 - add delete subcommand to AK
Fixes #6263 - rename assoc HC remove cmd BZ110467

In the associating command for Host Collection, this change renames
the 'remove-repository' command to 'remove-host-collection'
Merge pull request #193 from dustint-rh/rename_command_remove_host_collection

Fixes #6263 - rename associating HC remove cmd