Fix normalize pkg name

[raimon49]

This PR will fix #160

[codecov]

Codecov Report

Merging #161 (610cb3f) into master (925933d) will increase coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head 610cb3f differs from pull request most recent head a29e31b. Consider uploading reports for the commit a29e31b to get more accurate results

@@           Coverage Diff           @@
##           master     #161   +/-   ##
=======================================
  Coverage   99.06%   99.07%           
=======================================
  Files           1        1           
  Lines         430      433    +3     
=======================================
+ Hits          426      429    +3     
  Misses          4        4           

Impacted Files	Coverage Δ
piplicenses.py	99.07% <100.00%> (+<0.01%)	⬆️

[raimon49]

Shipped.
https://pypi.org/project/pip-licenses/4.3.1/