fix for issue #61

[mghiglieri]

Changed the order of SpecifiedProcuringProject to be conform to

<xs:complexType name="HeaderTradeAgreementType">
    <xs:sequence>
      <xs:element name="BuyerReference" type="udt:TextType" minOccurs="0"/>
      <xs:element name="SellerTradeParty" type="ram:TradePartyType"/>
      <xs:element name="BuyerTradeParty" type="ram:TradePartyType"/>
      <xs:element name="SalesAgentTradeParty" type="ram:TradePartyType" minOccurs="0"/>
      <xs:element name="BuyerTaxRepresentativeTradeParty" type="ram:TradePartyType" minOccurs="0"/>
      <xs:element name="SellerTaxRepresentativeTradeParty" type="ram:TradePartyType" minOccurs="0"/>
      <xs:element name="ProductEndUserTradeParty" type="ram:TradePartyType" minOccurs="0"/>
      <xs:element name="ApplicableTradeDeliveryTerms" type="ram:TradeDeliveryTermsType" minOccurs="0"/>
      <xs:element name="SellerOrderReferencedDocument" type="ram:ReferencedDocumentType" minOccurs="0"/>
      <xs:element name="BuyerOrderReferencedDocument" type="ram:ReferencedDocumentType" minOccurs="0"/>
      <xs:element name="QuotationReferencedDocument" type="ram:ReferencedDocumentType" minOccurs="0"/>
      <xs:element name="ContractReferencedDocument" type="ram:ReferencedDocumentType" minOccurs="0"/>
      <xs:element name="AdditionalReferencedDocument" type="ram:ReferencedDocumentType" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="BuyerAgentTradeParty" type="ram:TradePartyType" minOccurs="0"/>
      <xs:element name="SpecifiedProcuringProject" type="ram:ProcuringProjectType" minOccurs="0"/>
      <xs:element name="UltimateCustomerOrderReferencedDocument" type="ram:ReferencedDocumentType" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>

This fixes issue #61