add background image to drawer header

res/layout/drawer_header.xml

@@ -19,15 +19,15 @@
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
               android:layout_width="match_parent"
               android:layout_height="@dimen/nav_drawer_header_height"
-              android:background="@color/drawer_header_color">
+              android:background="@drawable/background"
+              android:fitsSystemWindows="true">
 
     <RelativeLayout
         android:id="@+id/drawer_active_user"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_gravity="bottom"
-        android:padding="@dimen/standard_padding"
-        >
+        android:padding="@dimen/standard_padding">
 
         <FrameLayout
             android:id="@+id/drawer_user_avatars"