add disco:variableQuantity on DataFile and LogicalDataSet ?

[boschthomas]

Pascal Heus (18.09.2014)

Just like we current have caseQuantity property on DataFile, could we also add a disco:variableQuantity on DataFile and LogicalDataSet. This is useful to have when:
(1) No variable level information is available
(2) only a stub of the RDF is requested
e.g when returning basic information on a Study of file, we do not need to return information on potentially hundreds or thousands of variables references or metadata

[boschthomas]

tasks:

• turtle [Thomas] [done]
• UML [Thomas] [done]
• html in appropriate sections [Thomas] [done]