[Authorize.net] Include phone/fax in billTo, add retail data for card pr...

This adds the `phoneNumber` and `faxNumber` fields to the `billTo` element in Authorize.net requests as defined in [their schema](https://api.authorize.net/xml/v1/schema/AnetApiSchema.xsd):
```xml
<xs:complexType name="customerAddressType">
  <xs:complexContent>
    <xs:extension base="anet:nameAndAddressType">
      <xs:sequence>
        <xs:element name="phoneNumber" minOccurs="0">
          <xs:simpleType>
            <xs:restriction base="xs:string">
              <xs:maxLength value="255"/>
            </xs:restriction>
          </xs:simpleType>
        </xs:element>
        <xs:element name="faxNumber" minOccurs="0">
          <xs:simpleType>
            <xs:restriction base="xs:string">
              <xs:maxLength value="255"/>
            </xs:restriction>
          </xs:simpleType>
        </xs:element>
      </xs:sequence>
    </xs:extension>
  </xs:complexContent>
</xs:complexType>
```

We [used to have `phone`](https://github.com/Shopify/active_merchant/blob/0b8a0de2e2d547b96e0d1aac63d5ace8baf0e9ff/lib/active_merchant/billing/gateways/authorize_net.rb#L306) but it appears to have been lost in the switchover to the new integration.

I also added the `retail` element with the `market_type` set to `2` which, as per their [Card Present Guide]( http://www.authorize.net/support/CP_guide.pdf), is currently the only available `market_type`. This fixes the failing remote test `test_card_present_authorize_and_capture_with_track_data_only`

@girasquid @ntalbott @jnormore 
so this will include market_type for card-not-present transactions too, is that intentional?