Extend information on array data types

[DavidFichtmueller]

Suggestion

There are several elements that have an array as their data type. Most of them are object properties with the names has, e.g. hasCitation or hasAgent. But could also be arrays of primitive types, as suggested in #168 , #174 and #175 . But in all cases, it would make the documentation a bit more useful to have it list the datatype of the objects contained in the array as well, e.g. "array of string" or "array of ods:Agent".

[ben-norton]

I concur with David's suggestion.