Detect <any /> element information

[veewee]

This PR introduces a new specialAny element type.

https://learn.microsoft.com/en-us/previous-versions/dotnet/netframework-4.0/ms256043(v=vs.100)

<any
  id = ID 
  maxOccurs = (nonNegativeInteger | unbounded) : 1
  minOccurs = nonNegativeInteger : 1 
  namespace = "(##any | ##other) | List of (anyURI | (##targetNamespace |  ##local))) : ##any 
  processContents = (lax | skip | strict) : strict 
  {any attributes with non-schema Namespace...}>
Content: (annotation?)
</any> 

<element name="GetCustomerDetailsResponse">
    <complexType>
        <sequence>
            <element name="customerName" type="xsd:string" />
            <element name="customerEmail" type="xsd:string" />
            <element name="customerData">
                <complexType>
                    <sequence>
                        <any processContents="lax" />
                    </sequence>
                </complexType>
            </element>
        </sequence>
    </complexType>
</element>

This new Any type can be used to acknowledge additional unkown XML elements can be available on the customerData element.

[goetas]

nothing to complain, looks good! :)

[veewee]

@goetas Just wondering : are you waiting on something specific to tag this?

[goetas]

oh, i forgot, done