Add alternative support for entity info aware over IExpando/IIndexable

[ioancrisan]

Currently the coupling between the entity and entity info is done through the IEntityInfoAware interface. As a fallback, it could also be done through setting a dynamic value

[ioancrisan]

Use a function to set the value, e.g.:
entity["_attachedEntityInfoGetter"] = () => entityInfo;
Thus, when serializing the entity, could skip the delegate properties.