[NLP2RDF] xsd:nonNegativeInteger for end and begin Index

[Sebastian Hellmann]

Hi all,
we had some discussion and decided to resolve the datatype issue like this:

When serializing you SHOULD add  xsd:nonNegativeInteger, i.e.

<#char=0,y> nif:beginIndex "0"^^xsd:nonNegativeInteger .

But you MAY choose to omit it to save space.


When parsing you MUST accept "0" as well as 
"0"^^xsd:nonNegativeInteger .
We advise developers however to be lenient and accept other compatible
xsd's as well, i.e. xsd:int

Any comments are highly welcome,
all the best,
Sebastian