[tracker] Add usageCounter property

[Ivan Frade <ifrade src gnome org>]

commit ea80106a6d9b6cf2e28f404c5ec6543aba96e3c0
Author: Ivan Frade <ivan frade nokia com>
Date:   Tue May 12 14:12:40 2009 +0300

    Add usageCounter property
    
    Add usageCounter property in NIE. This property can be used as
    play counter in music and videos, read counter in RSS and similar
    semantics in any other content.
---
 data/ontologies/30-nie.ontology |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/data/ontologies/30-nie.ontology b/data/ontologies/30-nie.ontology
index c2ba9e6..24b6405 100644
--- a/data/ontologies/30-nie.ontology
+++ b/data/ontologies/30-nie.ontology
@@ -239,3 +239,7 @@ nie:rootElementOf a rdf:Property ;
 	rdfs:domain nie:InformationElement ;
 	rdfs:range nie:DataSource .
 
+nie:usageCounter a rdf:Property ;
+	nrl:maxCardinality 1 ;
+	rdfs:domain nie:InformationElement ;
+	rdfs:range xsd:integer.