ARROW-5172: [Go] implement reading fixed-size binary arrays from Arrow file

[sbinet]

No description provided.

[sbinet]

needs #4158

[codecov-io]

Codecov Report

Merging #4159 into master will decrease coverage by 26.97%.
The diff coverage is 22.68%.

@@             Coverage Diff             @@
##           master    #4159       +/-   ##
===========================================
- Coverage   87.89%   60.91%   -26.98%     
===========================================
  Files         758       67      -691     
  Lines       92163     4943    -87220     
  Branches     1251        0     -1251     
===========================================
- Hits        81006     3011    -77995     
+ Misses      11040     1816     -9224     
+ Partials      117      116        -1

Impacted Files	Coverage Δ
go/arrow/ipc/file_reader.go	0% <0%> (ø)	⬆️
go/arrow/array/list.go	74.56% <0%> (-12.18%)	⬇️
go/arrow/ipc/metadata.go	0% <0%> (ø)	⬆️
go/arrow/array/struct.go	84.31% <100%> (+11.67%)	⬆️
go/arrow/array/fixedsize_binary.go	73.8% <79.16%> (+5.38%)	⬆️
go/arrow/memory/memory_avx2_amd64.go	0% <0%> (-100%)	⬇️
go/arrow/math/uint64_avx2_amd64.go	0% <0%> (-100%)	⬇️
go/arrow/math/int64_avx2_amd64.go	0% <0%> (-100%)	⬇️
go/arrow/math/float64_avx2_amd64.go	0% <0%> (-100%)	⬇️
go/arrow/memory/memory_amd64.go	28.57% <0%> (-14.29%)	⬇️
... and 701 more

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[sbinet]

PTAL @stuartcarnie @alexandreyc @nickpoorman

[sbinet]

(the Travis-CI error is unrelated (JDK-9 is acting up?))

[wesm]

https://issues.apache.org/jira/browse/ARROW-5223

[stuartcarnie]

LGTM