Merge branch 'MTO-37-new' into 'iteration2-pr-new'

MTO-37: [Variation] Checkout as Guest if Billing address != Shipping address

- Functional test implemented.

See merge request !93

Author: Vadim Zubovich

dev/tests/functional/tests/app/Magento/Checkout/Test/TestCase/OnePageCheckoutTest.xml

@@ -196,12 +196,13 @@
             <constraint name="Magento\Checkout\Test\Constraint\AssertOrderSuccessPlacedMessage" />
             <constraint name="Magento\Sales\Test\Constraint\AssertOrderGrandTotal" />
         </variation>
-        <variation name="OnePageCheckoutTestVariation9" summary="One Page Checkout Products with Tier Prices">
+        <variation name="OnePageCheckoutTestVariation9" summary="One Page Checkout Products with different shipping/billing address and Tier Prices" ticketId="MAGETWO-42604">
             <data name="tag" xsi:type="string">stable:no</data>
             <data name="products/0" xsi:type="string">catalogProductSimple::simple_with_tier_price_and_order_qty_3</data>
             <data name="customer/dataset" xsi:type="string">default</data>
             <data name="checkoutMethod" xsi:type="string">guest</data>
             <data name="shippingAddress/dataset" xsi:type="string">UK_address</data>
+            <data name="billingAddress/dataset" xsi:type="string">UK_address_2_without_email</data>
             <data name="shipping/shipping_service" xsi:type="string">Flat Rate</data>
             <data name="shipping/shipping_method" xsi:type="string">Fixed</data>
             <data name="prices" xsi:type="array">