FIX: 73f58dc56a broke XML variant of scripting console response, and will
  produce incompatible structure (extra nesting with scriptExec element).
  moved ScriptExecution code to ScriptModel, which is now a bean, not Map.
  XmlMarshaller is extended to support simple JavaBeans to XML marshalling,
  borrowing annotation classes from javax.xml.
ADD unit test for XmlMarshaller
revised scripting console xml response fix based on comments.
removed scripting console actions from ScriptModel into ScriptingConsole
class (resurrection of ScriptExec).
added basic ScriptingConsoleTest.
Merge branch 'topic/scripting-xml-fix'