Added booking of on demand trips (#13)

Added new requests to enable booking of on-demand transport:
   - Added AvailabilityRequest/-Response
   - Added BookingRequest/-Response
   - Added BookingCancellationRequest/-Response
   - Added BookingUpdateRequest/-Response

Moved HeavyLuggage from PassengerProfileGroup to new LuggageRequirementsGroup

Trias.xsd

@@ -97,7 +97,11 @@
  <xs:documentation>Choice of payload requests</xs:documentation>
  </xs:annotation>
  <xs:choice>
+ <xs:element ref="AvailabilityRequest"/>
  <xs:element ref="BookingInfoRequest"/>
+ <xs:element ref="BookingRequest"/>
+ <xs:element ref="BookingCancellationRequest"/>
+ <xs:element ref="BookingUpdateRequest"/>
  <xs:element ref="ConnectionDemandRequest"/>
  <xs:element ref="ConnectionDemandDeleteRequest"/>
  <xs:element ref="ConnectionReportRequest"/>
@@ -181,7 +185,11 @@
  <xs:documentation>Choice of delivery payload elements.</xs:documentation>
  </xs:annotation>
  <xs:choice>
+ <xs:element ref="AvailabilityResponse"/>
  <xs:element ref="BookingInfoResponse"/>
+ <xs:element ref="BookingResponse"/>
+ <xs:element ref="BookingCancellationResponse"/>
+ <xs:element ref="BookingUpdateResponse"/>
  <xs:element ref="ConnectionDemandResponse"/>
  <xs:element ref="ConnectionDemandDeleteResponse"/>
  <xs:element ref="ConnectionReportResponse"/>