[IMPROVEMENT] added Musixmatch lyrics source

[martinmake]

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Implements #2682

[pep8speaks]

Hello @martinmake! Thanks for updating this PR.

There are currently no PEP 8 issues detected in this Pull Request. Cheers! 🍻

Comment last updated at 2020-11-20 15:59:01 UTC

[codecov]

Codecov Report

Merging #2683 (34d2b6e) into master (bd46b35) will decrease coverage by 6.03%.
The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master    #2683      +/-   ##
==========================================
- Coverage   96.90%   90.86%   -6.04%     
==========================================
  Files           3        3              
  Lines         194      219      +25     
  Branches       21       24       +3     
==========================================
+ Hits          188      199      +11     
- Misses          5       17      +12     
- Partials        1        3       +2     

Impacted Files	Coverage Δ
swaglyrics/cli.py	80.76% <66.66%> (-11.64%)	⬇️

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[Mondonno]

I think this is good optimalization :) Maybe i change this soon