Add auto Twitter. Closes #2380

config/app.php

@@ -176,6 +176,7 @@ return [
         AltThree\Badger\BadgerServiceProvider::class,
         AltThree\Emoji\EmojiServiceProvider::class,
         AltThree\Logger\LoggerServiceProvider::class,
+        AltThree\Twitter\TwitterServiceProvider::class,
         BackupManager\Laravel\Laravel5ServiceProvider::class,
         Barryvdh\Cors\ServiceProvider::class,
         Fideloper\Proxy\TrustedProxyServiceProvider::class,

config/markdown.php

@@ -39,7 +39,10 @@ return [
     |
     */
 
-    'extensions' => env('CACHET_EMOJI', false) ? ['AltThree\Emoji\EmojiExtension'] : [],
+    'extensions' => array_filter([
+        env('CACHET_EMOJI', false) ? 'AltThree\Emoji\EmojiExtension' : null,
+        env('CACHET_AUTO_TWITTER', true) ? 'AltThree\Twitter\TwitterExtension' : null,
+    ]),
 
     /*
     |--------------------------------------------------------------------------