Issue-20_DevTools: Adding dev tools to .travis.yml

[manelbdcosta]

Link to issue

List of changes:

• Added lint stage to .travis.yml that installs and runs pre-commit
• Added .pre-commit-config.yaml* which will run the following hooks: Black, isort, mixed-line ending and trailing-whitespace
• Ran each of the tools individually (1 per commit to facilitate review 🙂) in order to achieve a passing travis build **

* The setup of .pre-commit-config.yaml was based off of the example given by @erwanp in the aforementioned issue (see the example here ** @erwanp let me know if you prefer do this step yourself - I understand it might be a bit overwhelming to see 20 files changed in a PR. Happy to revert the changes from this step!

[codecov[bot]]

Codecov Report

Merging #27 (92494ed) into master (5ebf104) will decrease coverage by 0.19%. The diff coverage is 79.85%.

@@            Coverage Diff             @@
##           master      #27      +/-   ##
==========================================
- Coverage   81.09%   80.89%   -0.20%     
==========================================
  Files          13       13              
  Lines         603      602       -1     
==========================================
- Hits          489      487       -2     
- Misses        114      115       +1     

Impacted Files	Coverage Δ
pytexit/test/__init__.py	100.00% <ø> (ø)
register.py	0.00% <0.00%> (ø)
setup.py	0.00% <0.00%> (ø)
setuptips.py	0.00% <0.00%> (ø)
pytexit/core/docx.py	83.33% <66.66%> (ø)
pytexit/pytexit.py	80.76% <68.42%> (-1.05%)	:arrow_down:
pytexit/test/test_docx.py	79.16% <76.92%> (ø)
pytexit/test/test_functions.py	78.49% <85.71%> (-0.86%)	:arrow_down:
pytexit/core/core.py	90.54% <87.83%> (-0.03%)	:arrow_down:
pytexit/__init__.py	100.00% <100.00%> (ø)
... and 7 more

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[erwanp]

No problem with modifying all the files, thank you for doing it. Merging !