Add some missing sub-resources.

These are only available as attributes of other resources and are
not directly accessible through the API, but defining them makes
it easier to create them to add to other resources.

lib/shopify_api/resources.rb

@@ -1,4 +1,5 @@
 require 'shopify_api/resources/base'
+require 'shopify_api/resources/address'
 require 'shopify_api/resources/application_charge'
 require 'shopify_api/resources/article'
 require 'shopify_api/resources/asset'
@@ -16,18 +17,23 @@ require 'shopify_api/resources/image'
 require 'shopify_api/resources/line_item'
 require 'shopify_api/resources/metafield'
 require 'shopify_api/resources/note_attribute'
+require 'shopify_api/resources/option'
 require 'shopify_api/resources/order'
 require 'shopify_api/resources/page'
+require 'shopify_api/resources/payment_details'
 require 'shopify_api/resources/product'
 require 'shopify_api/resources/product_search_engine'
 require 'shopify_api/resources/province'
+require 'shopify_api/resources/receipt'
 require 'shopify_api/resources/recurring_application_charge'
 require 'shopify_api/resources/redirect'
+require 'shopify_api/resources/rule'
 require 'shopify_api/resources/script_tag'
 require 'shopify_api/resources/shipping_address'
 require 'shopify_api/resources/shipping_line'
 require 'shopify_api/resources/shop'
 require 'shopify_api/resources/smart_collection'
+require 'shopify_api/resources/tax_line'
 require 'shopify_api/resources/theme'
 require 'shopify_api/resources/transaction'
 require 'shopify_api/resources/variant'

lib/shopify_api/resources/address.rb

@@ -0,0 +1,4 @@
+module ShopifyAPI
+  class Address < Base
+  end
+end

lib/shopify_api/resources/option.rb

@@ -0,0 +1,4 @@
+module ShopifyAPI
+  class Option < Base
+  end
+end

lib/shopify_api/resources/payment_details.rb

@@ -0,0 +1,4 @@
+module ShopifyAPI
+  class PaymentDetails < Base
+  end
+end

lib/shopify_api/resources/receipt.rb

@@ -0,0 +1,4 @@
+module ShopifyAPI
+  class Receipt < Base
+  end
+end

lib/shopify_api/resources/rule.rb

@@ -0,0 +1,4 @@
+module ShopifyAPI
+  class Rule < Base
+  end
+end

lib/shopify_api/resources/tax_line.rb

@@ -0,0 +1,4 @@
+module ShopifyAPI
+  class TaxLine < Base
+  end
+end