AQL expressions provided by default cannot work

[sbegaudeau]

As discussed before, since we now have moved the tools in a palette where they should be used some default expressions cannot work anymore such as aql:semanticEdgeSource.defaultCreateEdge(edgeDescription, semanticEdgeTarget)

Variables like nodeDescription and edgeDescription cannot be provided since they represent some magic coupling that we would have figured out in order to provide some default behavior. We cannot find out magically what the specifier expect and thus we cannot create a generic default behavior. We should probably remove them.