change field-spec-of to force 'type' and allow entity-or-type as argument
change field-spec-of to force 'type' and allow entity-or-type as argument

This change is needed for references.  When using get-reference, grab, grab-in
you pass the entity and those functions use 'field-spec-of' to get the correct document.
'field-spec-of' returned nil because entity was being sent not type.

wilkes/karras