Bump go versions in CI; update README

[markphelps]

RONSEAL

[codecov-io]

Codecov Report

Merging #264 into master will not change coverage by %.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #264   +/-   ##
=======================================
  Coverage   83.33%   83.33%           
=======================================
  Files          19       19           
  Lines        1638     1638           
=======================================
  Hits         1365     1365           
  Misses        186      186           
  Partials       87       87           

Impacted Files	Coverage Δ
server/server.go	82.92% <ø> (ø)

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