SCB-1059 Support go 1.11.2

[little-cui]

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[coveralls]

Coverage increased (+0.03%) to 61.822% when pulling 4863401 on little-cui:docker into 0e8562e on apache:master.

[codecov-io]

Codecov Report

Merging #504 into master will increase coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #504      +/-   ##
==========================================
+ Coverage   59.34%   59.35%   +<.01%     
==========================================
  Files         166      166              
  Lines       13945    13945              
==========================================
+ Hits         8276     8277       +1     
  Misses       5081     5081              
+ Partials      588      587       -1

Impacted Files	Coverage Δ
server/plugin/pkg/registry/etcd/tracing.go	72.72% <0%> (-9.1%)	⬇️
pkg/tlsutil/tlsutil.go	73.58% <0%> (-0.95%)	⬇️
server/broker/service.go	57.94% <0%> (+0.15%)	⬆️
server/broker/util.go	53.47% <0%> (+0.26%)	⬆️
server/govern/service.go	72.93% <0%> (+0.33%)	⬆️

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