Error if Service call returns collection of Result DTOs

[donaldgray]

A null reference exception is being thrown if a Service call returns a generic collection (e.g. IEnumerable).

E.g.

// This is fine
public ReturnDto Any(RequestDto){}

// As is this
public ReturnDto[] Any(RequestDto){}

// This is not
public IEnumerable<ReturnDto> Any(RequestDto){}

The issue is the call to Type.GetElementType() is returning null when the resourceType is an IEnumerable collection (PropertyEnricherManager ln46).

Type.GetElementType() is for Array types, need to update to use Type.GetGenericArguments if IEnumerable. See http://stackoverflow.com/questions/7072088/why-does-type-getelementtype-return-null