TVB-2719 lint: Use same convention everywhere

[ayan-b]

Closes #60

[ayan-b]

I used black to format the code.

[codecov]

Codecov Report

Merging #63 into trunk will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##             trunk       #63   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            1         1           
  Lines           72        72           
=========================================
  Hits            72        72           

Impacted Files	Coverage Δ
gdist.pyx	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 da6c8f5...0f400ad. Read the comment docs.

[liadomide]

These changes look good for the Python part. How about the Cython part of this library? Is there a cython lint tool which we could apply?

[ayan-b]

Modified flake8 configuration to enable linting for cython files.

[liadomide]

Would it be possible to copy with every ignored error code also the explanation for it (what we are ignoring).
e.g. E501 # Line too long (82 > 79 characters) ?

[liadomide]

Is E402 | Module level import not at top of file ?
Usually I don't like the stile of an import in another place that the top, unless there is a good reason. Do we really need this exception here?

[liadomide]

Also are these the ignores we really want:
E225 | Missing whitespace around operator E226 | Missing whitespace around arithmetic operator E227 | Missing whitespace around bitwise or shift operator
They would seem fitting to be obeyed, to me.

[ayan-b]

Also are these the ignores we really want:
E225 | Missing whitespace around operator E226 | Missing whitespace around arithmetic operator E227 | Missing whitespace around bitwise or shift operator
They would seem fitting to be obeyed, to me.

For pyx files, flake8 will complain for the pointers (treated as multiplication operator in python) and address-of operator (bitwise and operator in python).

Is E402 | Module level import not at top of file ?
Usually I don't like the stile of an import in another place that the top, unless there is a good reason. Do we really need this exception here?

Flake8 treats the cimports as non-import code and thus complains about the subsequent imports as imports not being on the top.

Would it be possible to copy with every ignored error code also the explanation for it (what we are ignoring).
e.g. E501 # Line too long (82 > 79 characters) ?

Done.