Pin proto / gogo versions for repeatable builds

[yurishkuro]

Undo some upgrades introduced in #940. A short term fix to #985.

[yurishkuro]

https://travis-ci.org/jaegertracing/jaeger/jobs/415593435 failed with

=== RUN   TestKafkaStorage/GetTrace
panic: runtime error: invalid memory address or nil pointer dereference [recovered]
	panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0xb3c342]
goroutine 15 [running]:
testing.tRunner.func1(0xc42034a0f0)
	/home/travis/.gimme/versions/go1.10.linux.amd64/src/testing/testing.go:742 +0x567
panic(0xfcc0e0, 0x16eed60)
	/home/travis/.gimme/versions/go1.10.linux.amd64/src/runtime/panic.go:505 +0x24a
github.com/jaegertracing/jaeger/model.SortTrace(0x0)
	/home/travis/gopath/src/github.com/jaegertracing/jaeger/model/sort.go:51 +0x42
github.com/jaegertracing/jaeger/plugin/storage/integration.CompareTraces(0xc42034a0f0, 0xc420312280, 0x0)
	/home/travis/gopath/src/github.com/jaegertracing/jaeger/plugin/storage/integration/domain_trace_compare_test.go:51 +0x7f
github.com/jaegertracing/jaeger/plugin/storage/integration.(*StorageIntegration).testGetTrace(0xc4202e4060, 0xc42034a0f0)
	/home/travis/gopath/src/github.com/jaegertracing/jaeger/plugin/storage/integration/integration_test.go:191 +0x356
github.com/jaegertracing/jaeger/plugin/storage/integration.(*StorageIntegration).(github.com/jaegertracing/jaeger/plugin/storage/integration.testGetTrace)-fm(0xc42034a0f0)
	/home/travis/gopath/src/github.com/jaegertracing/jaeger/plugin/storage/integration/integration_test.go:381 +0x4c
testing.tRunner(0xc42034a0f0, 0xc42004c250)
	/home/travis/.gimme/versions/go1.10.linux.amd64/src/testing/testing.go:777 +0x16e
created by testing.(*T).Run
	/home/travis/.gimme/versions/go1.10.linux.amd64/src/testing/testing.go:824 +0x565
FAIL	github.com/jaegertracing/jaeger/plugin/storage/integration	6.308s

@davit-y @vprithvi do you think it's protobuf-related or just an unstable test?

[codecov]

Codecov Report

Merging #984 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff          @@
##           master   #984   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files         139    139           
  Lines        6400   6400           
=====================================
  Hits         6400   6400

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[vprithvi]

I think this test is unstable, I was able to get it to fail locally without the protobuf changes.

[isaachier]

According to @vprithvi we should reconsider #985.