FromTTL: add support for Lists of primitives

[alelom]

Description:

Currently, Lists of primitives are translated to TTL by using the short notation, e.g. a List<int> containing values 0, 1, 2 will be tranlsated to ("0"^^rdf:int, "1"^^rdf:int,"2"^^rdf:int).

When translating from TTL back to objects, we are using RDFDotNet to gather the values of triples, however for some reason the list translated with that shorthand format is not correctly picked.

We can either:

• switch to the non-shorthand format for translating the list and try again with RDFDotNet
• for the single case of lists of primitives, find an alternative to RDFDotNet (perhaps parsing the text?)

[alelom]

Note that this is the reason why we have some tests failing ATM: