Create dropzone.md

Author: mhughes2k

docs/guides/javascript/modules/dropzone.md

@@ -0,0 +1,29 @@
+---
+title: Dropzone
+---
+<Since version="4.4" issueNumber="MDL-80850" />
+
+The use of the `core/dropzone` module provides a simplified developer experience for creating drop zones within Moodle.
+
+The module attempts to ensure that accessibility requirements are met, including applying the correct styles and keyboard navigation.
+
+Drop zones will trigger callbacks for common actions that occur within the drop zone for other code to listen to and react accordingly.
+
+```js title="Example of creating a dropzone"
+import Dropzone from 'core/dropzone';
+
+// Get the element that will be the dropzone.
+const dropZoneContainer = document.querySelector('#dropZoneId');
+// Create a new dropzone accepting only images.
+const dropZone = new Dropzone(
+    dropZoneContainer,
+    'image/*',
+    function(files) {
+        window.console.log(files);
+    }
+);
+// Set the custom message for the dropzone. Otherwise, it will use the default message.
+dropZone.setLabel('Drop images here');
+// Initialising the dropzone.
+dropZone.init();
+```