Provide possibility to use key ids

[DasJott]

JWT provides a possibility to use multiple secrets and specify the used one in its header field "kid".
Providing a map here to use that functionality.

[codecov]

Codecov Report

Merging #1289 into master will increase coverage by 0.04%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1289      +/-   ##
==========================================
+ Coverage   84.18%   84.22%   +0.04%     
==========================================
  Files          26       26              
  Lines        1948     1953       +5     
==========================================
+ Hits         1640     1645       +5     
  Misses        202      202              
  Partials      106      106

Impacted Files	Coverage Δ
middleware/jwt.go	80.72% <100%> (+1.23%)	⬆️

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[DasJott]

Explanation of the kid header param

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[DasJott]

Anyone?

[vishr]

@DasJott Thanks for your contribution 👍and sorry about the delay.

[DasJott]

You're welcome!
Very pleased to see it merged in 😊