adds show method to dropdown component (#80)

* adds show method to dropdown component.

* adds descriptions for using show and hide with dropdown

README.md

@@ -187,6 +187,13 @@ If you want a dropdown to be opened on page load you can set the ```data-dropdow
 </div>
 ```
 
+the code above will toggle the dropdown component, if you needed to only perform a single action, such as `show` or `hide`. the dropdown component exposes such method.
+
+```html
+data-action="click->dropdown#show"
+data-action="click->dropdown#hide"
+```
+
 Animations for the dropdown menu (like the TailwindUI dropdowns) can be applied using these data attributes:
 
 ```html

src/dropdown.js

@@ -123,6 +123,10 @@ export default class extends Controller {
         this.toggle()
     }
   }
+
+  show(){
+     this.openValue = true;
+  }
 
   hide(event) {
     if (this.element.contains(event.target) === false && this.openValue) {