Remove empty strings in Russian traduction in order to fallback on the English
ones.
<?xml version="1.0" encoding="utf-8"?>
<resources>
<color name="blue_sky">#A0C8FF</color>
<color name="vert_manu">#CCFF00</color>
<color name="black">#000000</color>
<color name="white">#FFFFFF</color>
<color name="red">#FF0000</color>
</resources>