IPAAnsibleModule: Provide base configuration for delete_continue.

Allows the creation of IPAAnsibleModule objects with specific
`ipa_arguments` which are defined in a dictionary of argumets in
the base class.

Every module using `delete_continue` should provide the proper behavior
and the module must be instantiated with:

  ansible_module = IPAAnsibleModule(
      ...,
      ipa_arguments=["delete_continue"]
  )

The plugin documentation must be extended with
'ipamodule_arguments.delete_continue'.