(feature): user can add custom key map

[AndreyMiloserdov]

No description provided.

[coveralls]

Pull Request Test Coverage Report for Build 726

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 78.947%

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Totals
Change from base Build 714:	0.0%
Covered Lines:	191
Relevant Lines:	211

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💛 - Coveralls

[codecov-commenter]

Codecov Report

Merging #222 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #222   +/-   ##
=======================================
  Coverage   90.52%   90.52%           
=======================================
  Files           1        1           
  Lines         211      211           
=======================================
  Hits          191      191           
  Misses         20       20           

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[jaywcjlove]

@AndreyMiloserdov Can you improve the documentation?

[CourtHive]

Is this ever going to move forward?

[jaywcjlove]

@CourtHive I think it is possible.