use a darker BG at big contact photo viewing

Author: tibbi

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

@@ -409,7 +409,7 @@
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:alpha="0"
-        android:background="#88000000"
+        android:background="#BB000000"
         android:clickable="true"
         android:padding="@dimen/activity_margin"
         android:scaleType="fitCenter"