Transition to MQT QFR

[burgholzer]

At the moment, the SyReC library uses its own gate and circuit class. However, the project readily build upon our QFR library (mainly for the external dependencies). It should be rather straight-forward to replace the SyReC classes with the respective Operations (Toffoli's are just multi-controlled X gates, Fredkin gates are multi-controlled SWAP gates).

The QFR library also already features a .real file parser. At the moment this does not handle constant and garbage values properly (see cda-tum/mqt-core#88). However, this should be easy to fix.

The simulation routine should be straight-forward to adapt as well.

I also see no real obstacle for the synthesis method to be refactored to use the QFR library.

One major change considers the Python bindings. At the moment, the QFR library does not provide Python bindings for the QuantumComputation class (see cda-tum/mqt-core#89). This is most certainly required for refactoring the SyReC-editor.

It might be required to get rid of some of the Boost dependencies first (see #27), such as the dependency on boost::signal2.