Updated Plugin Architecture (markdown)

Plugin-Architecture.md

@@ -44,14 +44,14 @@ It has been initially produced as part of [Issue #87](https://github.com/markche
 
 ## Plugin Source Root Directories
 
-| File Name | Description |
+| Dir. Name | Description |
 |------|-------------|
 | `class/` | Contains the Plugin PHP code, providing most of its functionality. |
 | `css/` | Contains the Plugin stylesheets. |
 | `img/` | Contains images used by the Plugin (@todo can this be merged with the root `assets/` dir?). |
 | `js/` | Contains JavaScript files used by the Plugin. |
 | `languages/` | Contains Plugin translation files for various languages. |
-| `templates/` | Contains HTML template files used by the Plugin. |
+| `templates/` | Contains HTML template files used by the Plugin to render various page elements. |
 
 ## `class/` Sub-directory
 
@@ -73,6 +73,26 @@ Important files are highlighted in **bold** text.
 
 ### `class/` Sub-directories
 
+| Dir. Name | Description |
+|------|-------------|
+| `dashboard/` | Contains the files that handle dashboard page construction. |
+| `widgets/` | Contains the files that handle widget construction. |
+
+### `class/dashboard/` Sub-sub-directory
+
+#### `class/dashboard/` Files
+
 | File Name | Description |
 |------|-------------|
-| `footnotes.php` | The Plugin entry point. |
+| `init.php` | Initialises the Plugin settings page. |
+| `layout.php` | Defines a common interface for rendering dashboard pages (@todo merge with `subpage-main.php`) |
+| `subpage-main.php` | Defines the Plugin settings page layout. |
+
+### `class/widgets/` Sub-sub-directory
+
+#### `class/widgets/` Files
+
+| File Name | Description |
+|------|-------------|
+| `base.php` | Defines a base class for all widgets. |
+| `reference-container.php` | Defines the Reference Container widget. |