fix inline simpleType restriction resolving to string instead of base type

Elements with inline <simpleType><restriction base="..."> were not
resolving the base type, defaulting to string. Added SimpleType field
to wsdl.Element and resolve the restriction base in genElementField.

Fixes #146.

Author: fiorix

wsdl/types.go

@@ -195,6 +195,7 @@ type Element struct {
 	Max         string       `xml:"maxOccurs,attr"` // can be # or unbounded
 	Nillable    bool         `xml:"nillable,attr"`
 	ComplexType *ComplexType `xml:"complexType"`
+	SimpleType  *SimpleType  `xml:"simpleType"`
 }
 
 // AnyElement describes an element of an undefined type.

wsdlgo/encoder.go

@@ -1705,6 +1705,9 @@ func (ge *goEncoder) genElementField(w io.Writer, el *wsdl.Element) {
 		}
 	}
 	et := el.Type
+	if et == "" && el.SimpleType != nil && el.SimpleType.Restriction != nil {
+		et = el.SimpleType.Restriction.Base
+	}
 	if et == "" {
 		et = "string"
 	}