Trivial golint fixes

[knweiss]

Please review.

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[knweiss]

Please see #40 regarding the Travis-CI failure.

[brancz]

Same as in #45 .

@knweiss you also need to sign the CLA for us to be able to merge these changes. Also even if flaky I'd prefer to see the tests pass.

[knweiss]

@brancz done

[googlebot]

CLAs look good, thanks!

[codecov-io]

Codecov Report

Merging #44 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master     #44   +/-   ##
======================================
  Coverage    77.4%   77.4%           
======================================
  Files           8       8           
  Lines         270     270           
======================================
  Hits          209     209           
  Misses         52      52           
  Partials        9       9

Impacted Files	Coverage Δ
client_metrics.go	74.44% <ø> (ø)	⬆️

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[brancz]

lgtm

[bwplotka]

nice