✨ Add measurements to mapped circuit

[burgholzer]

This PR adds the functionality to include measurements in mapped circuits according to the stored output permutation.
Furthermore, the qubit registers of the mapped circuit are now unified into a single register, similar to how this is handled in Qiskit.

It also fixes some smaller bugs:

• 🐛 fixed issue where output results in exact mapper were not instantiated correctly
• 🐛 fixed the computation of the IO mapping in both mappers which is required for correct dumping

[codecov]

Codecov Report

Merging #50 (d5fffa3) into main (f557687) will increase coverage by 0.4%.
The diff coverage is 95.6%.

@@           Coverage Diff           @@
##            main     #50     +/-   ##
=======================================
+ Coverage   88.2%   88.7%   +0.4%     
=======================================
  Files         21      22      +1     
  Lines       1613    1660     +47     
=======================================
+ Hits        1424    1473     +49     
+ Misses       189     187      -2     

Impacted Files	Coverage Δ
include/Mapper.hpp	51.6% <ø> (ø)
src/Mapper.cpp	94.0% <87.5%> (-1.7%)	⬇️
src/exact/ExactMapper.cpp	97.8% <100.0%> (+1.2%)	⬆️
src/heuristic/HeuristicMapper.cpp	94.0% <100.0%> (+<0.1%)	⬆️
include/exact/ExactMapper.hpp	100.0% <0.0%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update f557687...d5fffa3. Read the comment docs.