Fixed linter warning
Added support to bypass the prompts by passing the required information on the command line.  This allows the generator to be used by a script without user interaction.

I've added command options templateType, publisherName and publicationName.  All are optional and the user will be prompted for any that have not been passed on the command line.

The help now shows:
↪ yo pugpig --help
Usage:
  yo pugpig [options]

Options:
  -h,   --help             # Print generator's options and usage                   Default: false
  -t,   --templateType     # The template type. One of: Static, Drupal, Wordpress  Default: false
        --publisherName    # The publisher name                                    Default: false
        --publicationName  # The publication name                                  Default: false