travis: update go versions

[dvrkps]

No description provided.

[codecov-io]

Codecov Report

Merging #36 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #36   +/-   ##
=======================================
  Coverage   74.66%   74.66%           
=======================================
  Files           5        5           
  Lines         592      592           
=======================================
  Hits          442      442           
  Misses        136      136           
  Partials       14       14

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[nbrownus]

Thanks!