Bump version to 1.18.0

[raimon49]

• Implement function
• Testing
• Add a document
• Bump version
• Release to PyPI

This release is related to #51 and #52

[codecov]

Codecov Report

Merging #53 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master     #53   +/-   ##
======================================
  Coverage    97.9%   97.9%           
======================================
  Files           1       1           
  Lines         334     334           
======================================
  Hits          327     327           
  Misses          7       7

Impacted Files	Coverage Δ
piplicenses.py	97.9% <100%> (ø)	⬆️

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