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/reference/api/part/copy/en.md

@@ -0,0 +1,19 @@
+---
+title: copy()
+---
+
+```js
+Part part.copy(Part original)
+```
+
+This will copy the points, paths, and snippets from a part you pass into it.
+
+<Note>
+
+This method is used internally, you are unlikely to need this.
+
+If you want one part to build on another, you should set 
+up [part inheritance](/advanced/inject)  in your pattern's [configuration](../config) file.
+
+</Note>
+