🎁 Add works generator

This is a quality of life improvement.  Use this generator to create a
new work type in the Knapsack because using the Hyrax work generator
will create files in the submodule and we don't want that.

```sh
rails generate hyku_knapsack:work WorkType
```

config/initializers/hyrax.rb

@@ -0,0 +1,4 @@
+# Use this to override any Hyrax configuration from the Knapsack
+
+Hyrax.config do |config|
+end

lib/generators/hyku_knapsack/work/work_resource_generator.rb

@@ -0,0 +1,130 @@
+# frozen_string_literal: true
+
+# This is a copy of the Hyrax work generate adapted for use in the Knapsack.
+# example:
+#   `bundle exec rails generate hyku_knapsack:work_resource WorkType`
+#
+# This will ensure the generated files get created in the knapsack and not the submodule
+require 'rails/generators'
+require 'rails/generators/model_helpers'
+
+class HykuKnapsack::WorkResourceGenerator < Rails::Generators::NamedBase
+  # ActiveSupport can interpret models as plural which causes
+  # counter-intuitive route paths. Pull in ModelHelpers from
+  # Rails which warns users about pluralization when generating
+  # new models or scaffolds.
+  include Rails::Generators::ModelHelpers
+
+  TEMPLATE_PATH = Hyrax::Engine.root.join('lib', 'generators', 'hyrax', 'work_resource', 'templates')
+  source_root File.expand_path(TEMPLATE_PATH, __FILE__)
+
+  argument :attributes, type: :array, default: [], banner: 'field:type field:type'
+
+  def self.exit_on_failure?
+    true
+  end
+
+  def validate_name
+    return unless name.strip.casecmp("work").zero?
+    raise Thor::MalformattedArgumentError,
+          set_color("Error: A work resource with the name '#{name}' would cause name-space clashes. "\
+                    "Please use a different name.", :red)
+  end
+
+  def banner
+    if revoking?
+      say_status("info", "DESTROYING VALKYRIE WORK MODEL: #{class_name}", :blue)
+    else
+      say_status("info", "GENERATING VALKYRIE WORK MODEL: #{class_name}", :blue)
+    end
+  end
+
+  def create_controller
+    template('controller.rb.erb', File.join('../../app/controllers/hyrax', class_path, "#{plural_file_name}_controller.rb"))
+  end
+
+  def create_metadata_config
+    template('metadata.yaml', File.join('../config/metadata/', "#{file_name}.yaml"))
+    return if attributes.blank?
+    gsub_file File.join('config/metadata/', "#{file_name}.yaml"),
+              'attributes: {}',
+              { 'attributes' => attributes.collect { |arg| [arg.name, { 'type' => arg.type.to_s }] }.to_h }.to_yaml
+  end
+
+  def create_model
+    template('work.rb.erb', File.join('../app/models/', class_path, "#{file_name}.rb"))
+  end
+
+  def create_model_spec
+    return unless rspec_installed?
+    filepath = File.join('../../spec/models/', class_path, "#{file_name}_spec.rb")
+    template('work_spec.rb.erb', filepath)
+    return if attributes.blank?
+    inject_into_file filepath, after: /it_behaves_like 'a Hyrax::Work'\n/ do
+      "\n  context 'includes schema defined metadata' do\n"\
+      "#{attributes.collect { |arg| "    it { is_expected.to respond_to(:#{arg.name}) }\n" }.join}" \
+      "  end\n"
+    end
+  end
+
+  def create_form
+    template('form.rb.erb', File.join('../app/forms/', class_path, "#{file_name}_form.rb"))
+  end
+
+  # Inserts after the last registered work, or at the top of the config block
+  def register_work
+    config = '../config/initializers/hyrax.rb'
+    lastmatch = nil
+    in_root do
+      File.open(config).each_line do |line|
+        lastmatch = line if line.match?(/config.register_curation_concern :(?!#{file_name})/)
+      end
+      content = "  # Injected via `rails g hyrax:work_resource #{class_name}`\n" \
+                "  config.register_curation_concern #{registration_path_symbol}\n"
+      anchor = lastmatch || "Hyrax.config do |config|\n"
+      inject_into_file config, after: anchor do
+        content
+      end
+    end
+  end
+
+  def create_indexer
+    template('indexer.rb.erb', File.join('../app/indexers/', class_path, "#{file_name}_indexer.rb"))
+  end
+
+  def create_indexer_spec
+    return unless rspec_installed?
+    filepath = File.join('../spec/indexers/', class_path, "#{file_name}_indexer_spec.rb")
+    template('indexer_spec.rb.erb', filepath)
+  end
+
+  def create_views
+    create_file File.join('../app/views/hyrax', class_path, "#{plural_file_name}/_#{file_name}.html.erb") do
+      "<%# This is a search result view %>\n" \
+      "<%= render 'catalog/document', document: #{file_name}, document_counter: #{file_name}_counter  %>\n"
+    end
+  end
+
+  def create_view_spec
+    return unless rspec_installed?
+    template('work.html.erb_spec.rb.erb',
+             File.join('../spec/views/', class_path, "#{plural_file_name}/_#{file_name}.html.erb_spec.rb"))
+  end
+
+  private
+
+  def rspec_installed?
+    defined?(RSpec) && defined?(RSpec::Rails)
+  end
+
+  def registration_path_symbol
+    return ":#{file_name}" if class_path.blank?
+    # creates a symbol with a path like "abc/scholarly_paper" where abc
+    # is the namespace and scholarly_paper is the resource name
+    ":\"#{File.join(class_path, file_name)}\""
+  end
+
+  def revoking?
+    behavior == :revoke
+  end
+end