New design for the widgets section in the docs (#866)

* Initial commit for the new widgets section

* Placing all the widgets and refining the CSS and Hugo logic

* Initial commit for the new widgets section

* Placing all the widgets and refining the CSS and Hugo logic

* Rebased and updated the info according to @verythorough contribution

* Fixing the yaml codes for the relation and select widget sections

* Merging with widgets.md and app.j

* Fixing some silly mistakes (sorry!)

* Following @verythorough contributions :)

* Adding the markdown widget and fixing the widgets container background

* Adding the URL functionality and myself as a contributor :)

* Adding myself as a contributor :)

website/site/content/docs/widgets/markdown.md

@@ -0,0 +1,27 @@
+---
+label: "Markdown"
+target: "markdown"
+type: "widget"
+---
+
+### Markdown
+
+The markdown widget provides a full fledged text editor - which is based on [slate](https://github.com/ianstormtaylor/slate) - that allows users to format text with features such as headings and blockquotes. Users are also allowed to write in markdown by simply flipping a switch.
+
+*Please note:* in case you want to use your markdown editor to fill a markdown's file content after the frontmatter, you'll have name the field as `body` so then the CMS can recognize it and save the file accordingly.
+
+- **Name:** `markdown`
+- **UI:** full text editor
+- **Data type:** markdown
+- **Options:**
+  - `default`: accepts markdown content
+- **Example:**
+
+  ```yaml
+  - {label: "Blog post content", name: "body", widget: "markdown"}
+  ```
+
+This would render as:
+
+![Markdown widget example](/img/widgets-markdown.png)
+