feat: Flat import of markdown repo

This is a flat (without history) import of (some of) the content
from our markdown module.

We've imported this without history because the repo contains our
blog posts and showcases posts content prior to porting them to strapi.

Since this contains many images, it would balloon the size of this repo
to import the full history.

Instead, please refer to the history of the (archived) markdown repo
at: https://github.com/freesewing/markdown

markdown/dev/howtos/code/create-new-design/en.md

@@ -0,0 +1,42 @@
+---
+title: Creating a new pattern design
+for: developers
+about: Shows you how to create a new design
+---
+
+To create a new pattern, call `new freesewing.Design()`.
+It takes your pattern configuration, 
+and any plugins you want to load as parameters.
+
+For example, if we were creating a new pattern called `Sorcha`:
+
+```js
+import freesewing from "@freesewing/core"
+import plugins from "@freesewing/plugin-bundle"
+import config from "../config"
+
+// Create new design
+const Sorcha = new freesewing.Design(config, plugins)
+```
+
+This method does not return a `Design` object. Instead it returns 
+a constructor method for your pattern.
+
+When importing your pattern, it is itself a constructor:
+
+```js
+import Sorcha from "@freesewing/sorcha"
+
+// Sorcha is a constructor for your pattern. 
+let pattern = new Sorcha()
+```
+
+<Tip>
+
+##### Design() is a super-constructor
+
+Constructors are functions you can call with `new` to create an object. 
+As `freesewing.Design()` returns a constructor, you can think of it
+as a super-constructor.
+
+</Tip>