README.md in request_handler-0.12.0 vs README.md in request_handler-0.13.0

@@ -144,146 +144,22 @@
 ```ruby
 include_options = [:posts__comments]
 sort_options = SortOption.new(:posts__published_on, :asc)
 ```
 
-### Included relations
-
-Sometimes you want to create a single resource with its relations in a single
-request, ensuring that everything or nothing at all is created.  However, the
-current JSON API specification does not mention anything about how to achieve
-this at all, it is expected that all associated resources already exist.  
-`request_handler` attempts to solve this problem by allowing the request body
-to contain an `included` array with all the resources that have to be created.
-
-#### Example
-
-With this request handler:
-
-```ruby
-class CreateQuestionHandler < RequestHandler::Base
-  options do
-    body do
-      schema(
-        Dry::Validation.JSON do
-          required(:id).filled(:str?)
-          required(:type).filled(:str?)
-          required(:content).filled(:str?)
-
-          optional(:media).schema do
-            required(:id).filled(:str?)
-            required(:type).filled(:str?)
-          end
-        end
-      )
-
-      included do
-        media(
-          Dry::Validation.JSON do
-            required(:id).filled(:str?)
-            required(:type).filled(:str?)
-            required(:url).filled(:str?)
-
-            optional(:categories).schema do
-              required(:id).filled(:str?)
-              required(:type).filled(:str?)
-            end
-          end
-        )
-      end
-    end
-  end
-
-  def to_dto
-    # see the resulting body_params below
-    { body: body_params }
-  end
-end
-```
-
-The following JSON object including its included items is validated with the
-defined schema:
-
-``` json
-{
-  "data": {
-    "id": "1",
-    "type": "questions",
-    "attributes": {
-      "content": "How much is the fish?"
-    },
-    "relationships": {
-      "media": {
-          "data": {
-            "id": "image-123456",
-            "type": "media"
-          }
-        }
-      }
-    }
-  },
-  "included": [
-    {
-      "id": "image-123456",
-      "type": "media",
-      "attributes": {
-        "url": "https://example.com/fish.jpg"
-      },
-      "relationships": {
-        "categories": {
-          "data": {
-            "id": "123",
-            "type": "categories"
-          }
-        }
-      }
-    }
-  ]
-}
-```
-
-The resulting `body_params` will be this:
-
-``` ruby
-[
-  # The first object is the main resource object, i.e. the one that is about to
-  # be created
-  {
-    id:      '1',
-    type:    'questions',
-    content: 'How much is the fish?'
-    media:   [
-      {
-        id:   'image-123456',
-        type: 'media'
-      }
-    ]
-  },
-  # The remaining objects are every included object, validated with the schema
-  # defined above
-  {
-    id:         'image-123456',
-    type:       'media',
-    url:        'https://example.com/fish.jpg',
-    categories: {
-      id:   '123',
-      type: 'categories'
-    }
-  }
-]
-```
-
 ### Multipart requests
 It is also possible to process and validate multipart requests, consisting of an arbitrary number of parts.
+You can require specific resources, all the other listed resources are optional
 
-The following request handler accepts a question (which will be uploaded as a json-file) and an additional 
+The following request handler requires a question (which will be uploaded as a json-file) and accepts an additional 
 file related to the question
 
 ```ruby
 class CreateQuestionHandler < RequestHandler::Base
   options do
     multipart do
       question do
+        required true
         schema(
           Dry::Validation.JSON do
             required(:id).filled(:str?)
             required(:type).filled(:str?)
             required(:content).filled(:str?)