Updating multiline circuit draw

[scarrazza]

Closes #353. @igres26 could you please give a try and let me know if you like it?

[igres26]

Thanks for implementing this. The extra qubit labels work as I asked, and make the circuit more easily interpreted. I am still unsure if 70 is the correct line_wrap for most users but it looks good on my end. Could probably push it to 75 or 80, but that will depend on the user, so I think its fine.

[codecov]

Codecov Report

Merging #354 (452de4b) into master (f45dd66) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master      #354   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           76        76           
  Lines        12468     12473    +5     
=========================================
+ Hits         12468     12473    +5     

Flag	Coverage Δ
unittests	100.00% <100.00%> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
src/qibo/tests_new/test_abstract_circuit.py	100.00% <ø> (ø)
src/qibo/abstractions/circuit.py	100.00% <100.00%> (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 f45dd66...452de4b. Read the comment docs.