Fix documentation and add presentation (#30)

* Fix OpenAPI description

* Update limitations

* Add presentation

Author: truizlop

Documentation.app/Contents/MacOS/Generation examples.playground/Pages/Limitations.xcplaygroundpage/Contents.swift

@@ -21,5 +21,5 @@
 
  ## Body parameters encoding
 
- Currently, the only supported encoding for body parameters is `application/json`.
+ Currently, the only supported encodings for body parameters are `application/json` and `application/x-www-form-urlencoded`.
  */

Documentation.app/Contents/MacOS/Generation examples.playground/Pages/Parameters.xcplaygroundpage/Contents.swift

@@ -18,6 +18,7 @@
  info:
    title: My Store
    version: "1.0.0"
+ paths:
    /{category}/product:
      get:
        tags:

Documentation.app/Contents/MacOS/Quick start.playground/Pages/Resources.xcplaygroundpage/Contents.swift

@@ -19,7 +19,7 @@
 
  ## Presentations
 
- Be the first one showing here!
+ - Functional Networking ([slides](https://speakerdeck.com/truizlop/functional-networking-the-directors-cut), [video](https://www.dotconferences.com/2020/02/tomas-ruiz-lopez-functional-networking))
 
  ## Blog posts