readme: Update according to go doc

[goreadme]

No description provided.

[codecov]

Codecov Report

Merging #30 into master will increase coverage by 12.5%.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           master    #30      +/-   ##
========================================
+ Coverage    87.5%   100%   +12.5%     
========================================
  Files           1      1              
  Lines          16     16              
========================================
+ Hits           14     16       +2     
+ Misses          1      0       -1     
+ Partials        1      0       -1

Impacted Files	Coverage Δ
dialer.go	100% <0%> (+12.5%)	⬆️

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