add missing check for plugins

assets/about.html

@@ -31,6 +31,7 @@ function show(n) {
 
 <b>1.0.52</b>
 - <b>NEW</b> Files can now be sorted
+- <b>FIX</b> Display 'Plugins' option only if plugins are installed
 
 <b>1.0.51</b>
 - <b>FIX</b> Read MIDI files

src/ch/blinkenlights/android/vanilla/FullPlaybackActivity.java

@@ -303,7 +303,11 @@ public class FullPlaybackActivity extends SlidingPlaybackActivity
 		SubMenu moreMenu = menu.addSubMenu(0, MENU_MORE, 30, R.string.more_from_current);
 		menu.addSubMenu(0, MENU_ADD_TO_PLAYLIST, 30, R.string.add_to_playlist);
 		menu.add(0, MENU_SHARE, 30, R.string.share);
-		menu.add(0, MENU_PLUGINS, 30, R.string.plugins);
+
+		if (PluginUtils.checkPlugins(this)) {
+			menu.add(0, MENU_PLUGINS, 30, R.string.plugins);
+		}
+
 		mFavorites = menu.add(0, MENU_SONG_FAVORITE, 0, R.string.add_to_favorites).setIcon(R.drawable.btn_rating_star_off_mtrl_alpha).setShowAsActionFlags(MenuItem.SHOW_AS_ACTION_IF_ROOM);
 
 		// Subitems of 'enqueue...'