Bringing the QSIM code up-to-date with recent advances in PGC.

* [QSIM,SC] Simplified export code (new APIs).
* [QSIM,FIX] Make use of the new export options (new APIs).
* [QSIM_BUILD,FIX] Numbers cannot be used as literal (add_state/2).
* [QSIM_EXPORT,O] Added determinism for finding labels.
* [QSIM_WEB,SC] Vastly simplified export code (new APIs).
Merge branch 'master' of https://github.com/wouterbeek/WebQR