Added community packages to docs (#6167)

Co-authored-by: Guy Carmeli <guyca@users.noreply.github.com>

website/docs/community-libraries.mdx

@@ -0,0 +1,19 @@
+---
+id: community-libraries
+title: Community libraries
+sidebar_label: Community libraries
+---
+
+React Native Navigation has an active community with a bunch of support libraries.
+
+[React Native Navigation Hooks](https://github.com/underscopeio/react-native-navigation-hooks) :
+A set of React hooks for React Native Navigation.
+
+[React Native Navigation Drawer Extension](https://github.com/lukebrandonfarrell/react-native-navigation-drawer-extension) :
+Drawer API built on top of React Native Navigation for iOS and Android. 
+
+[React Native Navigation Search Bar](https://github.com/lukebrandonfarrell/react-native-navigation-search-bar) :
+React Native Elements search bar with collapsible header built for React Native Navigation.
+
+[React Native Navigation Register Screens](https://github.com/karlmarxlopez/react-native-navigation-register-screens) : 
+Utility function to register array of screens instead of calling `Navigation.registerComponent` multiple times.

website/sidebars.js

@@ -35,7 +35,8 @@ module.exports = {
     ],
     'Third party integration': [
       'third-party-react-context',
-      'third-party-mobx'
+      'third-party-mobx',
+      'community-libraries'
     ],
     Meta: [
       'meta-contributing'