[tracker] docs: Add example description file

[Carlos Garnacho <carlosg src gnome org>]

commit d9e9b5e1daf9b05c89bf14c2a5e85c3ec26a6e92
Author: Carlos Garnacho <carlosg gnome org>
Date:   Mon Aug 7 15:24:25 2017 +0200

    docs: Add example description file
    
    This was not added on git.

 .../examples/ontologies/example.description        |   16 ++++++++++++++++
 1 files changed, 16 insertions(+), 0 deletions(-)
---
diff --git a/docs/reference/libtracker-sparql/examples/ontologies/example.description 
b/docs/reference/libtracker-sparql/examples/ontologies/example.description
new file mode 100644
index 0000000..939c601
--- /dev/null
+++ b/docs/reference/libtracker-sparql/examples/ontologies/example.description
@@ -0,0 +1,16 @@
+@prefix dsc: <http://www.tracker-project.org/temp/dsc#> .
+
+<virtual-ontology-uri:30-nie.ontology> a dsc:Ontology ;
+       dsc:title "Example ontology" ;
+       dsc:description "A little bit of this and that." ;
+       dsc:upstream "http://www.example.org/ontologies";;
+       dsc:author "John doe, &lt;john example org&gt;";
+       dsc:editor "Jane doe, &lt;jane example org&gt;";
+       dsc:gitlog "http://git.example.org/cgit/tracker/log/example.ontology";;
+       dsc:contributor "someone else, &lt;some1 example org&gt;";
+
+       dsc:localPrefix "ex" ;
+       dsc:baseUrl "http://www.example.org/ontologies/ex#";;
+       dsc:relativePath "./10-ex.ontology" ;
+
+       dsc:copyright "All rights given away".