Update function-extensions.md

Author: Aklakan

docs/sparql-extensions/function-extensions.md

@@ -7,6 +7,8 @@ layout: default
 
 # SPARQL Function Extensions
 
-A function reference is available at [http://jsa.aksw.org/fn/](http://jsa.aksw.org/fn/).
+* Most functions are explained in the [Examples Section](https://github.com/SmartDataAnalytics/RdfProcessingToolkit/tree/develop/docs/examples).
+
+* A further function reference is available at [http://jsa.aksw.org/fn/](http://jsa.aksw.org/fn/).
 Note, that the functions are being consolidated into the new `norse` (Not Only Rdf Sparql Extensions) namespace `norse: <https://w3id.org/aksw/norse#>`.