Updated Plugins (markdown)

Plugins.md

@@ -148,6 +148,14 @@ There's no public API, later it could be created for some common extension point
 Plugins can have settings, they will look like this:
 ![](https://habrastorage.org/web/1db/a20/a07/1dba20a072904bdf8fb455d0900bb612.png)
 
+There are three types of settings:
+
+- text
+- select
+- checkbox
+
+To add settings, export `getSettings` function from your plugin and return the necessary settings config. You can find an example [here](https://github.com/keeweb/keeweb/blob/develop/plugins/examples/settings/plugin.js#L12).
+
 ## Guidelines
 
 - ❗️ DO NOT obfuscate, uglify, etc... plugin code, including styles and locales: it must be easy to read and review