GitLab

Add JsExpander that can be used to register additional functionality
in its qscriptengine and to evaluate expressions.

Register that with the VariableManager, using the "JS" prefix.

Change-Id: I7d8f1ddc3484104f3943685dbac09e786d60212e
Reviewed-by: Eike Ziller <eike.ziller@digia.com>