Add option to hide the stickers button in the composer

Signed-off-by: Aaron Raimist <aaron@raim.ist>

src/settings/Settings.ts

@@ -240,6 +240,11 @@ export const SETTINGS: {[setting: string]: ISetting} = {
         default: true,
         invertedSettingName: 'MessageComposerInput.dontSuggestEmoji',
     },
+    "MessageComposerInput.showStickersButton": {
+        supportedLevels: LEVELS_ACCOUNT_SETTINGS,
+        displayName: _td('Show stickers button'),
+        default: true,
+    },
     // TODO: Wire up appropriately to UI (FTUE notifications)
     "Notifications.alwaysShowBadgeCounts": {
         supportedLevels: LEVELS_ROOM_OR_ACCOUNT,