Fixed: Change extra keys and terminal input view background to black

Required for day/night theming and should fix issues where both views were translucent with light terminal color themes.

app/src/main/res/layout/activity_termux.xml

@@ -100,7 +100,7 @@
  android:visibility="gone"
  android:layout_width="match_parent"
  android:layout_height="37.5dp"
- android:background="@android:drawable/screen_background_dark_transparent"
+ android:background="@color/black"
  android:layout_alignParentBottom="true" />
 
  </RelativeLayout>