Add support for multiple pax types in MasterPricerTravelBoard

[therealartz]

Need an ability to define several pax types at once:

<ns1:paxReference>
    <ns1:ptc>ADT</ns1:ptc>
    <ns1:ptc>IIT</ns1:ptc>
    <ns1:traveller>
        <ns1:ref>1</ns1:ref>
    </ns1:traveller>
    <ns1:traveller>
        <ns1:ref>2</ns1:ref>
    </ns1:traveller>
</ns1:paxReference>

Tested with PRD env.

[coveralls]

Coverage increased (+9.0e-05%) to 99.851% when pulling d4fcc66 on therealartz:master into 2ea2952 on amabnl:master.

[DerMika]

So how does this work? In your test, you add "count = 1" and 2 pax types, and then it adds one pax type of each? Then the "count" property is no longer named very appropriately.

It's not very intuitive to me, but ok. If you add a sample to the docs and explain how to use it, we can merge it.

[therealartz]

@DerMika Amadeus returns us some specific private fares which is not getting returned by just asking unifares.

Of course I don't know how it will behave if ask to return ADT and CHD at once but when asking for this combination it works as expected.

However I don't see it strange since $ptc property already is mapped as an array. $this->ptc[] = $passengerType; it always was. Now we can pass not only one item there.

Added the sample.

[DerMika]

Allright, as long as it's in the docs, I'm fine with this change :)