Bug wrt. to GeneralEntryRequest and SEFFInterpretationContext

[stiesssh]

When creating a GeneralEntryRequest in caseExternalCallAction in the Seff Interpreter, we update the SEFFInterpretationContext with a caller, but we set the caller to the context itself (or rather a copy thereof), which, in my opinion makes no sense.

However, i dont know the impact of changing this self reference yet. We should discuss this @klinakuf.

(I drew a picture, but it's only on paper.)