Proper handling of internal errors #7

Many operations can fail, the SCXML standard requires that various error events be placed on the internal event queue when these failures occur. Support for this must be added for good conformance to the standard.

Example:
5.9.2 Location Expressions
Location expressions are used to specify a location in the data model, e.g. as part of the , , or elements. The exact nature of a location depends on the data model. If a location expression cannot be evaluated to yield a valid location, the SCXML processor must place the error 'error.execution' in the internal event queue.