Update title for metered preference

    <!-- Option for indicating that a network being metered (expensive) should be determined automatically. [CHAR LIMIT=32] -->

    <string name="data_usage_metered_auto">Automatic</string>

    <!-- Title for Network usage to control whether Wifi is metered or not [CHAR LIMIT=20] -->

    <string name="wifi_metered_title">Network usage</string>

    <!-- Option for indicating that a network is metered (expensive). [CHAR LIMIT=32] -->

    <string name="data_usage_metered_yes">Metered</string>

    <!-- Option for indicating that a network is not metered (inexpensive). [CHAR LIMIT=32] -->

    <DropDownPreference

        android:key="metered"

        android:icon="@drawable/ic_attach_money_black_24dp"

        android:title="@string/data_usage_metered_yes"

        android:title="@string/wifi_metered_title"

        android:entries="@array/wifi_metered_entries"

        android:entryValues="@array/wifi_metered_values"/>