The authors are supported by the DFG through the Collaborative Research Center SFB 912 – HAEC
the CRC/TR 248 – Foundations of Perspicuous Software Systems, the Excellence Initiative by the German Federal and State Governments (clusters of excellence cfaed and CeTI), the Research Training Group QuantLA (GRK 1763) and the DFG-projects BA-1679/11-1 and BA-1679/12-1.